Nt1210 Chapter 1

CHAPTER 1 INFORMATION TECHNOLOGY1.0 Introduction Information technology (IT) is the design, development, implementation, support, and management of computer hardware and software applications. An IT professional is knowledgeable about computer systems and operating systems. This chapter will review IT certifications and the components of a basic personal computer system.After completing this chapter, you will meet these objectives: * Explain IT industry certifications. * Describe a computer system. * Identify the names, purposes, and characteristics of cases and power supplies. * Identify the names, purposes, and characteristics of internal components. * Identify the names, purposes, and characteristics of ports and cables. * Identify
the names, purposes, and characteristics of input devices. * Identify the names, purposes, and characteristics of output devices. * Explain system resources and their purposes. 1.1 | | Explain IT industry certifications | | | This course will focus on desktop and laptop computers. It will also discuss electronic devices, such as personal digital assistants and cell phones.Training and experience will qualify a technician to service these computers and personal electronic devices. You will gain the specialized technical skills needed to install, maintain, and repair computers. Earning an industry-standard certification will give you confidence and increase your opportunities in IT.This course is focused on the following two industry-standard certifications: * CompTIA A+ * European Certification of Informatics Professional (EUCIP) IT Administrator Certification (Modules 1 and 2)After completing this section, you will meet these objectives: * Identify education and certifications. * Describe the A+ Certification. * Describe the EUCIP Certification. | | 1.1.1 | | Identify education and certifications | | | Information Technology (IT) is a term that encompasses the relationship between hardware, software, networks, and technical assistance provided to users. IT Essentials: PC Hardware and Software covers the information that a technician needs to be successful in IT. This course covers the following topics: * Personal computers * Safe lab procedures * Troubleshooting * Operating systems * Laptop computers * Printers and scanners * Networks * Security * Communication skillsThe IT Essentials course focuses on two hardware and software skills-based industry certifications: CompTIA A+ and EUCIP. This course is only an introduction into the world of IT. A technician may continue to study and earn the following certifications: * CCNA – Cisco Certified Networking Associate * CCNP – Cisco Certified Networking Professional * CCIE – Cisco Certified Internetworking Expert * CISSP – Certified Information Systems Security Professional * MCP – Microsoft Certified Professional * MCSA – Microsoft Certified Systems Administrator * MCSE – Microsoft Certified Systems Engineer * Network+ – CompTIA Network Certification * Linux+ – CompTIA Linux CertificationIT certifications can be used as credits for university and college degrees in areas such as computer science and telecommunications. | | | | 1.1.2 | | Describe the A+ certification | |

| Computing Technology Industry Association (CompTIA) developed the A+ Certification program. A CompTIA A+ certification, as shown in Figure 1, signifies that a candidate is a qualified PC hardware and software technician. CompTIA certifications are known throughout the IT community as one of the best ways to enter the information technology field and build a solid career.The latest version of CompTIA A+ is CompTIA A+ 2009 Edition. Two exams are necessary to be certified: CompTIA A+ Essentials, exam code 220-701; and CompTIA A+ Practical Application, exam code 220-702.CompTIA A+ Essentials measures the necessary competencies of an entry-level IT professional with at least 500 hours of hands-on experience in the lab or field. It tests for the fundamentals of computer technology, networking and security, as well as the communication skills and professionalism now required of all entry-level IT professionals.CompTIA A+ Practical Application is an extension of the knowledge and skills identified in CompTIA A+ Essentials, with more of a hands-on orientation focused on scenarios in which troubleshooting and tools must be applied to resolve problems. | | 1.1.3 | | Describe the EUCIP certification | |

| The EUCIP IT Administrator program offers a recognized certification of competence in IT. The certification covers the standards prescribed by the Council of European Professional Informatics Societies (CEPIS). The EUCIP IT Administrator Certification consists of five modules, with a corresponding exam for each module. This course will prepare you for Modules 1 and 2.Module 1: PC Hardware
The PC Hardware module requires that the candidate understand the basic makeup of a personal computer and the functions of the components. The candidate should be able to effectively diagnose and repair hardware problems. The candidate should be able to advise customers of the appropriate hardware to buy.Module 2: Operating Systems
The Operating Systems module requires that the candidate be familiar with the procedures for installing and updating most common operating systems and applications. The candidate should know how to use system tools for troubleshooting and repairing operating systems.Module 3: Local Area Network and Network Services
This module is beyond the scope of the IT Essentials course, although some of the topics are covered. The Local Area Network and Network Services module requires that the candidate be familiar with the procedure of installing, using, and managing local area networks. The candidate should be able to add and remove users and shared resources. The candidate should know how to use system tools for troubleshooting and repairing networks.Module 4: Expert Network Use
This module is beyond the scope of the IT Essentials course, although some of the topics are covered. The Expert Network Use module requires that the candidate understand LAN communication.Module 5: IT Security
This module is beyond the scope of the IT Essentials course, although some of the topics are covered. The IT Security module requires that the candidate be familiar with security methods and features that are available for a standalone or networked computer. | | 1.2 | | Describe a computer system | |

| A computer system consists of hardware and software components. Hardware is the physical equipment such as the case, storage drives, keyboards, monitors, cables, speakers, and printers. The term software includes the operating system and programs. The operating system instructs the computer how to operate. These operations may include identifying, accessing, and processing information. Programs or applications perform different functions. Programs vary widely depending on the type of information that will be accessed or generated. For example, instructions for balancing a checkbook are very different from instructions for simulating a virtual reality world on the Internet.The rest of this chapter discusses the hardware components found in a computer system. | | | Identify the names, purposes, and characteristics of cases and power supplies | |

| The computer case provides protection and support for the internal components of the computer. All computers need a power supply to convert alternating-current (AC) power from the wall socket into direct-current (DC) power. The size and shape of the computer case is usually determined by the motherboard and other internal components.You can select a large computer case to accommodate additional components that may be required in the future. Other users may select a smaller case that requires minimal space. In general, the computer case should be durable, easy to service, and have enough room for expansion.The power supply must provide enough power for the components that are currently installed and allow for additional components that may be added at a later time. If you choose a power supply that powers only the current components, it may be necessary to replace the power supply when other components are upgraded.After completing this section, you will meet these objectives: * Describe cases. * Describe power supplies. | | 1.3.1 | | Describe cases | |

| A computer case contains the framework to support the internal components of a computer while providing an enclosure for added protection. Computer cases are typically made of plastic, steel, and aluminum and are available in a variety of styles.The size and layout of a case is called a form factor. There are many types of cases, but the basic form factors for computer cases include desktop and tower. Desktop cases may be slimline or full-sized, and tower cases may be mini or full-sized, as shown in Figure 1.Computer cases are referred to in a number of ways: * Computer chassis * Cabinet * Tower * Box * HousingIn addition to providing protection and support, cases also provide an environment designed to keep the internal components cool. Case fans are used to move air through the computer case. As the air passes warm components, it absorbs heat and then exits the case. This process keeps the components of the computer from overheating.There are many factors that must be considered when choosing a case: * The size of the motherboard * The number of external or internal drive locations called bays * Available spaceSee Figure 2 for a list of features.In addition to providing protection from the environment, cases help to prevent damage from static electricity. Internal components of the computer are grounded by attachment to the case.NOTE: You should select a case that matches the physical dimensions of the power supply and motherboard. | | 1.3.2 | | Describe power supplies | |

| The power supply, shown in Figure 1, converts alternating-current (AC) power coming from a wall outlet into direct-current (DC) power, which is a lower voltage. DC power is required for all of the components inside the computer.A computer can tolerate slight fluctuations in power, but a significant deviation can cause the power supply to fail. An uninterruptible power supply (UPS) can protect a computer from problems caused by changes in power. A UPS provides power for a computer using a power inverter. A power inverter provides AC power to the computer from a built-in battery by converting the DC current of the UPS battery into AC power.Connectors
Most connectors today are keyed connectors. Keyed connectors are designed to be inserted in only one direction. Each part of the connector has a colored wire with a different voltage running through it, as seen in Figure 2. Different connectors are used to connect specific components to various ports on the motherboard: * A Molex connector is a keyed connector used to connect to an optical drive or a hard drive. * A Berg connector is a keyed connector used to connect to a floppy drive. A Berg connector is smaller than a Molex connector. * A 20-pin or 24-pin slotted connector is used to connect to the motherboard. The 24-pin slotted connector has two rows of 12 pins each, and the 20-pin slotted connector has two rows of 10 pins each. * A 4-pin to 8-pin auxiliary power connector has two rows of two to four pins and supplies power to all areas of the motherboard. The 4-pin to 8-pin auxiliary power connector is the same shape as the main power connector, but smaller. * Older standard power supplies used two connectors called P8 and P9 to connect to the motherboard. P8 and P9 were unkeyed connectors. They could be installed backwards, potentially damaging the motherboard or power supply. The installation required that the connectors were lined up with the black wires together in the middle.NOTE: If you have a difficult time inserting a connector, try a different way, or check to make sure that there are no bent pins or foreign objects in the way. Remember, if it seems difficult to plug in any cable or other part, something is wrong. Cables, connectors, and components are designed to fit together snugly. Never force any connector or component. The connectors that are plugged in incorrectly will damage the plug and the connector. Take your time and make sure that you are handling the hardware correctly.Electricity and Ohm's Law
These are the four basic units of electricity: * Voltage (V) * Current (I) * Power (P) * Resistance (R)Voltage, current, power, and resistance are electronic terms that a computer technician must know: * Voltage is a measure of the force required to push electrons through a circuit.
* Voltage is measured in volts (V). A computer power supply usually produces several different voltages. * Current is a measure of the amount of electrons going through a circuit. * Current is measured in amperes, or amps (A). Computer power supplies deliver different amperages for each output voltage. * Power is a measure of the pressure required to push electrons through a circuit, called voltage, multiplied by the number of electrons going through that circuit, called current. The measurement is called watts (W). Computer power supplies are rated in watts. * Resistance is the opposition to the flow of current in a circuit. Resistance is measured in ohms. Lower resistance allows more current, and therefore more power, to flow through a circuit. A good fuse will have low resistance or a measurement of almost 0 ohms.There is a basic equation that expresses how three of the terms relate to each other. It states that voltage is equal to the current multiplied by the resistance. This is known as Ohm's Law.V = IRIn an electrical system, power (P) is equal to the voltage multiplied by the current.P = VIIn an electrical circuit, increasing the current or the voltage will result in higher power.As an example of how this works, imagine a simple circuit that has a 9V light bulb hooked up to a 9V battery. The power output of the light bulb is 100W. Using the equation above, we can calculate how much current in amps would be required to get 100W out of this 9V bulb.To solve this equation, we know the following information: * P = 100W * V = 9V * I = 100W / 9V = 11.11AWhat happens if a 12V battery and a 12V light bulb are used to get 100W of power?100W / 12V = 8.33AThis
system produces the same power, but with less current.Computers normally use power supplies ranging from 250W to 650W output capacity. However, some computers may need 850W and higher capacity power supplies. When building a computer, select a power supply with sufficient wattage to power all of the components. Each component inside the computer uses a certain amount of power. Obtain the wattage information for the components from the manufacturer's documentation. When deciding on a power supply, make sure to choose a power supply that has more than enough power for the current components. A power supply with a higher wattage rating has more capacity; therefore, it can handle more devices.On the back of the power supply is a small switch called the voltage selector switch. This switch sets the input voltage to the power supply to either 110V / 115V or 220V / 230V. The correct voltage setting is determined by the country where the power supply will be used. Setting the voltage switch to the incorrect input voltage could damage the power supply and other parts of your computer. If a power supply does not have the voltage selector switch, your power supply will automatically detect and set the correct voltage.CAUTION: Do not open a power supply. Electronic capacitors located inside of a power supply, shown in Figure 3, can hold a charge for extended periods of time. | | 1.4 | | Identify the names, purposes, and characteristics of internal components | |

| This section discusses the names, purposes, and characteristics of the internal components of a computer.After completing this section, you will meet these objectives: * Identify the names, purposes, and characteristics of motherboards. * Explain the names, purposes, and characteristics of CPUs. * Identify the names, purposes, and characteristics of cooling systems. * Identify the names, purposes, and characteristics of ROM and RAM. * Identify the names, purposes, and characteristics of adapter cards. * Identify the names, purposes, and characteristics of storage drives. * Identify the names, purposes, and characteristics of internal cables. | | 1.4.1 | | Identify the names, purposes, and characteristics of motherboards | |

| The motherboard is the main printed circuit board and contains the buses, or electrical pathways, found in a computer. These buses allow data to travel between the various components that comprise a computer. Figure 1 shows a variety of motherboards. A motherboard is also known as the system board, the backplane, or the main board.The motherboard accommodates the central processing unit (CPU), RAM, expansion slots, heat sink/fan assembly, BIOS chip, chipset, and the embedded wires that interconnect the motherboard components. Sockets, internal and external connectors, and various ports are also placed on the motherboard. The form factor of motherboards pertains to the size and shape of the board. It also describes the physical layout of the different components and devices on the motherboard. The form factor determines how individual components attach to the motherboard and the shape of the computer case. Various form factors exist for motherboards, as shown in Figure 2.The most common form factor in desktop computers was the AT, based on the IBM AT motherboard. The AT motherboard can be up to approximately one foot wide. This cumbersome size led to the development of smaller form factors. The placement of heat sinks and fans often interferes with the use of expansion slots in smaller form factors.A newer motherboard form factor, ATX, improved on the AT design. The ATX case is designed to accommodate the integrated I/O ports on the ATX motherboard. The ATX power supply connects to the motherboard via a single 20-pin connector instead of the confusing P8 and P9 connectors used with some earlier form factors. Instead of using a physical toggle switch, the ATX power supply can be powered on and off using signaling from the motherboard.Some manufacturers have proprietary form factors based on the ATX design. This causes some motherboards, power supplies, and other components to be incompatible with standard ATX cases.An important set of components on the motherboard is the chipset. The chipset is composed of various integrated circuits attached to the motherboard that control how system hardware interacts with the CPU and motherboard. The CPU is installed into a slot or socket on the motherboard. The socket on the motherboard determines the type of CPU that can be installed.The chipset of a motherboard allows the CPU to communicate and interact with the other components of the computer, and to exchange data with system memory, or RAM, hard disk drives, video cards, and other output devices. The chipset establishes how much memory can be added to a motherboard. The chipset also determines the type of connectors on the motherboard.Most chipsets are divided into two distinct components, Northbridge and Southbridge. What each component does varies from manufacturer to manufacturer. In general, the Northbridge controls access to the RAM, video card, and the speeds at which the CPU can communicate with them. The video card is sometimes integrated into the Northbridge. AMD and Intel have chips that integrate the memory controller onto the CPU die, which improves performance and power consumption. The Southbridge, in most cases, allows the CPU to communicate with the hard drives, sound card, USB ports, and other I/O ports. | | 1.4.2 | | Identify the names, purposes, and characteristics of CPUs | |

| The central processing unit (CPU) is considered the brain of the computer. It is sometimes referred to as the processor. Most calculations take place in the CPU. In terms of computing power, the CPU is the most important element of a computer system. CPUs come in different form factors, each style requiring a particular slot or socket on the motherboard. Common CPU manufacturers include Intel and AMD.The CPU socket or slot is the connector that interfaces between the motherboard and the processor. Most CPU sockets and processors in use today are built around the pin grid array (PGA) architecture, in which the pins on the underside of the processor are inserted into the socket, usually with zero insertion force (ZIF). ZIF refers to the amount of force needed to install a CPU into the motherboard socket or slot. Slot-based processors are cartridge-shaped and fit into a slot that looks similar to an expansion slot. Figure 1 lists common CPU socket specifications.The CPU executes a program, which is a sequence of stored instructions. Each model of processor has an instruction set, which it executes. The CPU executes the program by processing each piece of data as directed by the program and the instruction set. While the CPU is executing one step of the program, the remaining instructions and the data are stored nearby in a special memory called cache. There are two major CPU architectures related to instruction sets: * Reduced Instruction Set Computer (RISC) – Architectures use a relatively small set of instructions, and RISC chips are designed to execute these instructions very rapidly. * Complex Instruction Set Computer (CISC) – Architectures use a broad set of instructions, resulting in fewer steps per operation.Some CPUs incorporate hyperthreading to enhance the performance of the CPU. With hyperthreading, the CPU has multiple pieces of code being executed simultaneously on each pipeline. To an operating system, a single CPU with hyperthreading performs as though there are two CPUs.The power of a CPU is measured by the speed and the amount of data that it can process. The speed of a CPU is rated in cycles per second. The speed of current CPUs is measured in millions of cycles per second, called megahertz (MHz), or billions of cycles per second, called gigahertz (GHz). The amount of data that a CPU can process at one time depends on the size of the processor data bus. This is also called the CPU bus or the front side bus (FSB). The wider the processor data bus width, the more powerful the processor is. Current processors have a 32-bit or a 64-bit processor data bus.Overclocking is a technique used to make a processor work at a faster speed than its original specification. Overclocking is not a reliable way to improve computer performance and can result in damage to the CPU. The opposite of overclocking is CPU throttling. CPU throttling is a technique used when the processor runs at less than the rated speed to conserve power or produce less heat. Throttling is commonly used on laptops and other mobile devices.MMX is a set of multimedia instructions built into Intel processors. MMX enabled microprocessors can handle many common multimedia operations that are normally handled by a separate sound or video card. However, only software specifically written to call MMX instructions can use the MMX instruction set. In Intel CPUs, MMX has been replaced by Streaming Single-instruction-multi-data Extensions (SSE), which is an enhancement to the instruction set. There are many versions of SSE, each of which includes additional instructions.The latest processor technology has resulted in CPU manufacturers finding ways to incorporate more than one CPU core onto a single chip. Figure 2 lists the most common multiple core processors. These CPUs are capable of processing multiple instructions concurrently: * Single Core CPU – One core inside a single CPU that handles all of the processing capability. A motherboard manufacturer may provide sockets for more than one single processor, providing the ability to build a powerful, multi-processor computer. * Dual Core CPU – Two cores inside a single CPU in which both cores can process information at the same time. * Triple Core CPU – Three cores inside a single CPU that is actually a quad-core processor with one of the cores disabled. * Quad Core CPU – Four cores inside a single CPU in which all cores can process information simultaneously for enhanced software applications. | | 1.4.3 | | Identify the names, purposes, and characteristics of cooling systems | |

| Electronic components generate heat. Heat is caused by the flow of current within the components. Computer components perform better when kept cool. If the heat is not removed, the computer may run slower. If too much heat builds up, computer components can be damaged.Increasing the air flow in the computer case allows more heat to be removed. A case fan, shown in Figure 1, is installed in the computer case to make the cooling process more efficient.In addition to case fans, a heat sink draws heat away from the core of the CPU. A fan on top of the heat sink, shown in Figure 2, moves the heat away from the CPU.Other components are also susceptible to heat damage and are sometimes equipped with fans. Video adapter cards also produce a great deal of heat. Fans are dedicated to cool the graphics-processing unit (GPU), as seen in Figure 3.Computers with extremely fast CPUs and GPUs may use a water-cooling system. A metal plate is placed over the processor and water is pumped over the top to collect the heat that the CPU creates. The water is pumped to a radiator to be cooled by the air, and then re-circulated. | |

1.4.4 | | Identify the names, purposes, and characteristics of ROM and RAM | |

| ROM
Read-only memory (ROM) chips are located on the motherboard. ROM chips contain instructions that can be directly accessed by the CPU. Basic instructions for booting the computer and loading the operating system are stored in ROM. ROM chips retain their contents even when the computer is powered down. The contents cannot be erased or changed by normal means. The different types of ROM are described in Figure 1.NOTE: ROM is sometimes called firmware. This is misleading because firmware is actually the software that is stored in a ROM chip.RAM
Random access memory (RAM) is the temporary storage for data and programs that are being accessed by the CPU. RAM is volatile memory, which means that the contents are erased when the computer is powered off. The more RAM in a computer, the more capacity the computer has to hold and process large programs and files, as well as enhance system performance. The different types of RAM are described in Figure 2.Memory Modules
Early computers had RAM installed on the motherboard as individual chips. The individual memory chips, called dual inline package (DIP) chips, were difficult to install and often became loose on the motherboard. To solve this problem, designers soldered the memory chips on a special circuit board called a memory module. The different types of memory modules are described in Figure 3.NOTE: Memory modules can be single-sided or double-sided. Single-sided memory modules only contain RAM on one side of the module. Double-sided memory modules contain RAM on both sides of the module.The speed of memory has a direct impact on how much data a processor can process because faster memory improves the performance of the processor. As processor speed increases, memory speed must also increase. For example, single-channel memory is capable of transferring data at 64 bits. Dual-channel memory increases speed by using a second channel of memory, creating a data transfer rate of 128 bits.Double Data Rate (DDR) technology doubles the maximum bandwidth of SDRAM. DDR2 offers faster performance while using less energy. DDR3 operates at even higher speeds than DDR2; however, none of these DDR technologies are backward- or forward-compatible. See Figure 4 for a chart comparing different memory types and speeds.Cache
SRAM is used as cache memory to store the most frequently used data. SRAM provides the processor with faster access to the data than retrieving it from the slower DRAM, or main memory. The three types of cache memory are described in Figure 5.Error Checking
Memory errors occur when the data is not stored correctly in the RAM chips. The computer uses different methods to detect and correct data errors in memory. Figure 6 describes three different methods of memory error checking. 1.4.5 | | Identify the names, purposes, and characteristics of adapter cards | | | Adapter cards increase the functionality of a computer by adding controllers for specific devices or by replacing malfunctioning ports. Figure 1 shows several types of adapter cards. Adapter cards are used to expand and customize the capability of the computer: * Network Interface Card (NIC) – Connects a computer to a network using a network cable * Wireless NIC – Connects a computer to a network using radio frequencies * Sound adapter – Provides audio capability * Video adapter – Provides graphic capability * Capture card – Sends a video signal to a computer so that the signal can be recorded to the computer hard drive with Video Capture software * TV tuner – Provides the ability to watch and record TV signals on a PC by connecting a TV source, such as cable TV, satellite, or an antenna, to the installed tuner card * Modem adapter – Connects a computer to the Internet using a phone line * Small Computer System Interface (SCSI) adapter – Connects SCSI devices, such as hard drives or tape drives, to a computer * Redundant Array of Independent Disks (RAID) adapter – Connects multiple hard drives to a computer to provide redundancy and to improve performance * Universal Serial Bus (USB) port – Connects a computer to peripheral devices * Parallel port – Connects a computer to peripheral devices * Serial port – Connects a computer to peripheral devicesComputers have expansion slots on the motherboard to install adapter cards. The type of adapter card connector must match the expansion slot. A riser card was used in computer systems with the LPX form factor to allow adapter cards to be installed horizontally. The riser card was mainly used in slim-line desktop computers. The different types of expansion slots are shown in Figure 2 | | 1.4.6 | | Identify the names, purposes, and characteristics of storage drives | | | Storage drives, as shown in Figure 1, read or write information to magnetic or optical storage media. The drive can be used to store data permanently or to retrieve information from a media disk. Storage drives can be installed inside the computer case, such as a hard drive. For portability, some storage drives can connect to the computer using a USB port, a FireWire port, or an SCSI port. These portable storage drives are sometimes referred to as removable drives and can be used on multiple computers. Here are some common types of storage drives: * Floppy drive * Hard drive * Optical drive * Flash driveFloppy Drive
A floppy drive, or floppy disk drive, is a storage device that uses removable 3.5-inch floppy disks. These magnetic floppy disks can store 720 KB or 1.44 MB of data. In a computer, the floppy drive is usually configured as the A: drive. The floppy drive can be used to boot the computer if it contains a bootable floppy disk. A 5.25-inch floppy drive is older technology and is seldom used.Hard Drive
A hard drive, or hard disk drive, is a magnetic storage device that is installed inside the computer. The hard drive is used as permanent storage for data. In a Windows computer, the hard drive is usually configured as the C: drive and contains the operating system and applications. The hard drive is often configured as the first drive in the boot sequence. The storage capacity of a hard drive is measured in billions of bytes, or gigabytes (GB). The speed of a hard drive is measured in revolutions per minute (RPM). Multiple hard drives can be added to increase storage capacity.Traditional hard drives are magnetic. Magnetic hard drives have drive motors designed to spin magnetic platters and the drive heads. In contrast, the newer solid state drives (SSDs) do not have moving parts. Because there are no drive motors and moving parts, the SSD uses far less energy than the magnetic hard drive. Non-volatile flash memory chips manage all storage on an SSD, which results in faster access to data, higher reliability, and reduced power usage. SSDs have the same form factor as magnetic hard drives and use ATA or SATA interfaces. SSDs can be installed as a replacement for magnetic drives.Optical Drive
An optical drive is a storage device that uses lasers to read data on the optical media. There are three types of optical drives: * Compact Disc (CD) * Digital versatile Disc (DVD) * Blu-ray Disc (BD)CD, DVD, and BD media can be pre-recorded (read-only), recordable (write once), or re-recordable (read and write multiple times). CDs have a data storage capacity of approximately 700 MB. DVDs have a data storage capacity of approximately 4.3 GB on a single-layer disc, and approximately 8.5 GB on a dual-layer disc. BDs have a storage capacity of 25 GB on a single-layer disc, and 50 GB on a dual-layer disc.There are several types of optical media: * CD-ROM – CD read-only memory media that is pre-recorded. * CD-R – CD recordable media that can be recorded one time. * CD-RW – CD rewritable media that can be recorded, erased, and re-recorded. * DVD-ROM – DVD read-only memory media that is pre-recorded. * DVD-RAM – DVD random access memory media that can be recorded, erased, and re-recorded. * DVD+/-R – DVD recordable media that can be recorded one time. * DVD+/-RW – DVD rewritable media that can be recorded, erased, and re-recorded. * BD-ROM – BD read-only media that is pre-recorded with movies, games, or software. * BD-R – BD recordable media that can record HD video and PC data storage one time. * BD-RE – BD rewritable format for HD video recording and PC data storage.External Flash Drive
An external flash drive, also known as a thumb drive, is a removable storage device that connects to a USB port. An external flash drive uses the same type of non-volatile memory chips as solid state drives and does not require power to maintain the data. These drives can be accessed by the operating system in the same way that other types of drives are accessed.Types of Drive Interfaces
Hard drives and optical drives are manufactured with different interfaces that are used to connect the drive to the computer. To install a storage drive in a computer, the connection interface on the drive must be the same as the controller on the motherboard. Here are some common drive interfaces: * IDE – Integrated Drive Electronics, also called Advanced Technology Attachment (ATA) is an early drive controller interface that connects computers and hard disk drives. An IDE interface uses a 40-pin connector. * EIDE – Enhanced Integrated Drive Electronics, also called ATA-2, is an updated version of the IDE drive controller interface. EIDE supports hard drives larger than 512 MB, enables Direct Memory Access (DMA) for speed, and uses the AT Attachment Packet Interface (ATAPI) to accommodate optical drives and tape drives on the EIDE bus. An EIDE interface uses a 40-pin connector. * PATA – Parallel ATA refers to the parallel version of the ATA drive controller interface. * SATA – Serial ATA refers to the serial version of the ATA drive controller interface. A SATA interface uses a 7-pin data connector. * eSATA – External Serial ATA provides a hot-swappable, external interface for SATA drives. The eSATA interface connects an external SATA drive using a 7-pin connector. The cable can be up to two meters (6.56 ft.) in length. * SCSI – Small Computer System Interface is a drive controller interface that can connect up to 15 drives. SCSI can connect both internal and external drives. An SCSI interface uses a 50-pin, 68-pin, or 80-pin connector.RAID provides a way to store data across multiple hard disks for redundancy. To the operating system, RAID appears as one logical disk. See Figure 2 for a comparison of the different RAID levels. The following terms describe how RAID stores data on the various disks: * Parity – A method used to detect data errors. * Striping – A method used to write data across multiple drives. * Mirroring – A method of storing duplicate data to a second drive. | | 1.4.7 | | Identify the names, purposes, and characteristics of internal cables | | | Drives require both a power cable and a data cable. A power supply will have a SATA power connector for SATA drives, a Molex power connector for PATA drives, and a Berg 4-pin connector for floppy drives. The buttons and the LED lights on the front of the case connect to the motherboard with the front panel cables.Data cables connect drives to the drive controller, which is located on an adapter card or on the motherboard. Here are some common types of data cables: * Floppy disk drive (FDD) data cable – Data cable has up to two 34-pin drive connectors and one 34-pin connector for the drive controller. * PATA (IDE/EIDE) 40-conductor data cable – Originally, the IDE interface supported two devices on a single controller. With the introduction of Extended IDE, two controllers capable of supporting two devices each were introduced. The 40-conductor ribbon cable uses 40-pin connectors. The cable has two connectors for the drives and one connector for the controller. * PATA (EIDE) 80-conductor data cable – As the data rates available over the EIDE interface increased, the chance of data corruption during transmission increased. An 80-conductor cable was introduced for devices transmitting at 33.3 MB/s and over, allowing for a more reliable balanced data transmission. The 80-conductor cable uses 40-pin connectors. * SATA data cable – This cable has seven conductors, one keyed connector for the drive, and one keyed connector the drive controller. * eSATA data cable – The eSATA external disk connects to the eSATA interface using a 7-pin data cable. This cable does not supply any power to the eSATA external disk. A separate power cable provides power to the disk. * SCSI data cable – There are three types of SCSI data cables. A narrow SCSI data cable has 50 conductors, up to seven 50-pin connectors for drives, and one 50-pin connector for the drive controller, also called the host adapter. A wide SCSI data cable has 68 conductors, up to 15 68-pin connectors for drives, and one 68-pin connector for the host adapter. An Alt-4 SCSI data cable has 80 conductors, up to 15 80-pin connectors for drives, and one 80-pin connector for the host adapter.NOTE: A colored stripe on a cable identifies Pin 1 on the cable. When installing a data cable, always ensure that Pin 1 on the cable aligns with Pin 1 on the drive or drive controller. Some cables may be keyed and therefore they can only be connected one way to the drive and drive controller. | | | | 1.5 | | Identify the names, purposes, and characteristics of ports and cables | |

| Input/output (I/O) ports on a computer connect peripheral devices, such as printers, scanners, and portable drives. The following ports and cables are commonly used: * Serial * USB * FireWire * Parallel * SCSI * Network * PS/2 * Audio * VideoSerial Ports and Cables
A serial port can be either a DB-9, as shown in Figure 1, or a DB-25 male connector. Serial ports transmit one bit of data at a time. To connect a serial device, such as a modem or printer, a serial cable must be used. A serial cable has a maximum length of 50 feet (15.2 m).Modem Ports and Cables
In addition to the serial cable used to connect an external modem to a computer, a telephone cable is used to connect a modem to a telephone outlet. This cable uses an RJ-11 connector, as shown in Figure 2. A traditional setup of an external modem using a serial cable and a telephone cable is shown in Figure 3.USB Ports and Cables
The Universal Serial Bus (USB) is a standard interface that connects peripheral devices to a computer. It was originally designed to replace serial and parallel connections. USB devices are hot-swappable, which means that users can connect and disconnect the devices while the computer is powered on. USB connections can be found on computers, cameras, printers, scanners, storage devices, and many other electronic devices. A USB hub is used to connect multiple USB devices. A single USB port in a computer can support up to 127 separate devices with the use of multiple USB hubs. Some devices can also be powered through the USB port, eliminating the need for an external power source. Figure 4 shows USB cables with connectors.USB 1.1 allowed transmission rates of up to 12 Mbps in full-speed mode and 1.5 Mbps in low-speed mode. USB 2.0 allows transmission speeds up to 480 Mbps. USB devices can only transfer data up to the maximum speed allowed by the specific port.FireWire Ports and Cables
FireWire is a high-speed, hot-swappable interface that connects peripheral devices to a computer. A single FireWire port in a computer can support up to 63 devices. Some devices can also be powered through the FireWire port, eliminating the need for an external power source. FireWire uses the IEEE 1394 standard and is also known as i.Link.The IEEE 1394a standard supports data rates up to 400 Mbps and cable lengths up to 15 feet (4.5 m). This standard uses a 6-pin connector or a 4-pin connector. The IEEE 1394b standard allows for a greater range of connections, including CAT5 UTP and optical fiber. Depending on the media used, data rates are supported up to 3.2 Gbps over a 100m distance. Figure 5 shows FireWire cables with connectors.Parallel Ports and Cables
A parallel port on a computer is a standard Type A DB-25 female connector. The parallel connector on a printer is a standard Type B 36-pin Centronics connector. Some newer printers may use a Type C high-density 36-pin connector. Parallel ports can transmit 8 bits of data at one time and use the IEEE 1284 standard. To connect a parallel device, such as a printer, a parallel cable must be used. A parallel cable, as shown in Figure 6, has a maximum length of 15 feet (4.5 m).SCSI Ports and Cables
A SCSI port can transmit parallel data at rates in excess of 320 MBps and can support up to 15 devices. If a single SCSI device is connected to an SCSI port, the cable can be up to 80 feet (24.4 m) in length. If multiple SCSI devices are connected to an SCSI port, the cable can be up to 40 (12.2 m) feet in length. An SCSI port on a computer can be one of three different types, as shown in Figure 7: * 80-pin connector * 50-pin connector * 68-pin connectorNOTE: SCSI devices must be terminated at the endpoints of the SCSI chain. Check the device manual for termination procedures.CAUTION: Some SCSI connectors resemble parallel connectors. Be careful not to connect the cable to the wrong port. The voltage used in the SCSI format may damage the parallel interface. SCSI connectors should be clearly labeled.Network Ports and Cables
A network port, also known as an RJ-45 port, connects a computer to a network. The connection speed depends on the type of network port. Standard Ethernet can transmit up to 10 Mbps, Fast Ethernet can transmit up to 100 Mbps, and Gigabit Ethernet can transmit up to 1000 Mbps. The maximum length of network cable is 328 feet (100 m). A network connector is shown in Figure 8.PS/2 Ports
A PS/2 port connects a keyboard or a mouse to a computer. The PS/2 port is a 6-pin mini-DIN female connector. The connectors for the keyboard and mouse are often colored differently, as shown in Figure 9. If the ports are not color-coded, look for a small figure of a mouse or keyboard next to each port.Audio Ports
An audio port connects audio devices to the computer. Some of the following audio ports are commonly used, as shown in Figure 10: * Line In – Connects to an external source, such as a stereo system * Microphone – Connects to a microphone * Line Out – Connects to speakers or headphones * Sony/Philips Digital Interface Format (S/PDIF) – Connects to fiber optic cable to support digital audio * TosLink – Connects to coaxial cable to support digital audio * Gameport/MIDI – Connects to a joystick or MIDI-interfaced deviceVideo Ports and Connectors
A video port connects a monitor cable to a computer. Figure 11 shows three common video ports. There are several video port and connector types: * Video Graphics Array (VGA) – VGA has a 3-row, 15-pin female connector and provides analog output to a monitor. * Digital Visual Interface (DVI) – DVI has a 24-pin female connector or a 29-pin female connector and provides an uncompressed digital output to a monitor. DVI-I provides both analog and digital signals. DVI-D provides digital signals only. * High-Definition Multimedia Interface (HDMi) – HDMi has a 19-pin connector and provides digital video and digital audio signals. * S-Video – S-Video has a 4-pin connector and provides analog video signals. * Component/RGB – RGB has three shielded cables (red, green, blue) with RCA jacks and provides analog video signals. | |

1.6 | | Identify the names, purposes, and characteristics of input devices | |

| An input device is used to enter data or instructions into a computer. Here are some examples of input devices: * Mouse and keyboard * Digital camera and digital video camera * Biometric authentication device * Touch screen * ScannerThe mouse and keyboard are the two most commonly used input devices. The mouse is used to navigate the graphical user interface (GUI). The keyboard is used to enter text commands that control the computer.A keyboard, video, mouse (KVM) switch is a hardware device that can be used to control more than one computer using a single keyboard, monitor, and mouse. KVM switches provide cost-efficient access to multiple servers using a single keyboard, monitor, and mouse for businesses. Home users can save space using a KVM switch to connect multiple computers to one keyboard, monitor, and mouse. See Figure 1.Newer KVM switches have added the capability to share USB devices and speakers with multiple computers. Typically, by pressing a button on the KVM switch, the user can change the control from one connected computer to another connected computer. Some models of the switch transfer control from one computer to another computer using a specific key sequence on a keyboard, such as CNTL > CNTL > A > ENTER to control the first computer connected to the switch, then CNTL > CNTL > B > ENTER to transfer control to the next computer.Digital cameras and digital video cameras, shown in Figure 2, create images that can be stored on magnetic media. The image is stored as a file that can be displayed, printed, or altered.Biometric identification makes use of features that are unique to an individual user, such as fingerprints, voice recognition, or a retinal scan. When combined with ordinary usernames, biometrics guarantees that the authorized person is accessing the data. Figure 3 shows a laptop that has a built-in fingerprint scanner. By measuring the physical characteristics of the fingerprint of the user, the user is granted access if the fingerprint characteristics match the database and the correct login information is supplied.A touch screen has a pressure-sensitive transparent panel. The computer receives instructions specific to the place on the screen that the user touches.A scanner digitizes an image or document. The digitization of the image is stored as a file that can be displayed, printed, or altered. A bar code reader is a type of scanner that reads universal product code (UPC) bar codes. It is widely used for pricing and inventory information. | | 1.7 | | Identify the names, purposes, and characteristics of output devices | |

| An output device is used to present information to the user from a computer. Here are some examples of output devices: * Monitors and projectors * Printers, scanners, and fax machines * Speakers and headphonesMonitors and Projectors
Monitors and projectors are primary output devices for a computer. There are different types of monitors, as shown in Figure 1. The most important difference between these monitor types is the technology used to create an image: * CRT – The cathode-ray tube (CRT) has three electron beams. Each beam directs colored phosphor on the screen that glows either red, blue, or green. Areas not struck by an electron beam do not glow. The combination of glowing and non-glowing areas creates the image on the screen. This technology is also used by most televisions. CRTs usually have a degauss button on the front that the user can press to remove discoloration caused by magnetic interference. * LCD – Liquid crystal display is commonly used in flat panel monitors, laptops, and some projectors. It consists of two polarizing filters with a liquid crystal solution between them. An electronic current aligns the crystals so that light can either pass through or not pass through. The effect of light passing through in certain areas and not in others is what creates the image. LCD comes in two forms, active matrix and passive matrix. Active matrix is sometimes called thin film transistor (TFT). TFT allows each pixel to be controlled, which creates very sharp color images. Passive matrix is less expensive than active matrix but does not provide the same level of image control. Passive matrix is not commonly used in laptops. * DLP – Digital light processing is another technology used in projectors. DLP projectors use a spinning color wheel with a microprocessor-controlled array of mirrors called a digital micromirror device (DMD). Each mirror corresponds to a specific pixel. Each mirror reflects light toward or away from the projector optics. This creates a monochromatic image of up to 1024 shades of gray in between white and black. The color wheel then adds the color data to complete the projected color image.Monitor resolution refers to the level of image detail that can be reproduced. Figure 2 is a chart of common monitor resolutions. Higher resolution settings produce better image quality. Several factors are involved in monitor resolution: * Pixel – The term pixel is an abbreviation for picture element. Pixels are the tiny dots that comprise a screen. Each pixel consists of red, green, and blue. * Dot pitch – Dot pitch is the distance between pixels on the screen. A lower dot pitch number produces a better image. * Contrast ratio – The contrast ratio is a measurement of the difference in intensity of light between the brightest point (white) and the darkest point (black). A 10,000:1 contrast ratio shows dimmer whites and lighter blacks than a monitor with a contrast ratio of 1,000,000:1. * Refresh rate – The refresh rate is how often per second the image is rebuilt. A higher refresh rate produces a better image and reduces the level of flicker. * Interlace/Non-Interlace – Interlaced monitors create the image by scanning the screen two times. The first scan covers the odd lines, top to bottom, and the second scan covers the even lines. Non-interlaced monitors create the image by scanning the screen, one line at a time from top to bottom. Most CRT monitors today are non-interlaced. * Horizontal Vertical Colors (HVC) – The number of pixels in a line is the horizontal resolution. The number of lines in a screen is the vertical resolution. The number of colors that can be reproduced is the color resolution. * Aspect ratio – Aspect ratio is the horizontal to vertical measurement of the viewing area of a monitor. For example, a 4:3 aspect ratio would apply to a viewing area that is 16 inches wide by 12 inches high. A 4:3 aspect radio would also apply to a viewing area that is 24 inches wide by 18 inches high. A viewing area that is 22 inches wide by 12 inches high has an aspect ratio of 11:6. * Native resolution – Native resolution is the number of pixels that a monitor has. A monitor with a resolution of 1280x1024 has 1280 horizontal pixels and 1024 vertical pixels. Native mode is when the image sent to the monitor matches the native resolution of the monitor.Monitors have controls for adjusting the quality of the image. Here are some common monitor settings: * Brightness – Intensity of the image * Contrast – Ratio of light to dark * Position – Vertical and horizontal location of image on the screen * Reset – Returns the monitor settings to factory settingsAdding additional monitors increases the number of windows that are visible on the desktop. Many computers have built-in support for multiple monitors. See Figure 3 for more information about configuring multiple monitors.All-in-One Printer
Printers are output devices that create hard copies of computer files. Some printers specialize in particular applications, such as printing color photographs. Other all-in-one type printers, like the one shown in Figure 4, are designed to provide multiple services such as printing, scanning, faxing, and copying.Speakers and Headphones
Speakers and headphones are output devices for audio signals. Most computers have audio support either integrated into the motherboard or on an adapter card. Audio support includes ports that allow input and output of audio signals. The audio card has an amplifier to power headphones and external speakers, which are shown in Figure 5. | | 1.8 | | Explain system resources and their purposes | |

| System resources are used for communication purposes between the CPU and other components in a computer. There are three common system resources: * Interrupt Requests (IRQ) * Input/Output (I/O) Port Addresses * Direct Memory Access (DMA)Interrupt Requests
IRQs are used by computer components to request information from the CPU. The IRQ travels along a wire on the motherboard to the CPU. When the CPU receives an interrupt request, the CPU determines how to fulfill this request. The priority of the request is determined by the IRQ number assigned to that computer component. Older computers only had eight IRQs to assign to devices. Newer computers have 16 IRQs, which are numbered 0 to 15, as shown in Figure 1. As a general rule, each component in the computer must be assigned a unique IRQ. IRQ conflicts can cause components to stop functioning and even cause the computer to crash. Today, most IRQ numbers are assigned automatically with plug and play (PnP) operating systems and the implementation of PCI slots, USB ports, and FireWire ports. With the numerous components that can be installed in a computer, it is difficult to assign a unique IRQ to every component. PCI devices can now share IRQs without conflict.Input/Output (I/O) Port Addresses
Input/output (I/O) port addresses are used to communicate between devices and software. The I/O port address is used to send and receive data for a component. As with IRQs, each component will have a unique I/O port assigned. There are 65,535 I/O ports in a computer, and they are referenced by a hexadecimal address in the range of 0000h to FFFFh. Figure 2 shows a chart of common I/O ports.Direct Memory Access
DMA channels are used by high-speed devices to communicate directly with main memory. These channels allow the device to bypass interaction with the CPU and directly store and retrieve information from memory. Only certain devices can be assigned a DMA channel, such as SCSI host adapters and sound cards. Older computers only had four DMA channels to assign to components. Newer computers have eight DMA channels that are numbered 0 to 7, as shown in Figure 3. | | 1.9 | | Summary | |

| This chapter introduced the IT industry, options for training and employment, and some of the industry-standard certifications. This chapter also covered the components that comprise a personal computer system. Much of the content in this chapter will help you throughout this course: * Information Technology encompasses the use of computers, network hardware, and software to process, store, transmit, and retrieve information. * A personal computer system consists of hardware components and software applications. * The computer case and power supply must be chosen carefully to support the hardware inside the case and allow for the addition of components. * The internal components of a computer are selected for specific features and functions. All internal components must be compatible with the motherboard. * You should use the correct type of ports and cables when connecting devices. * Typical input devices include the keyboard, mouse, touch screen, and digital cameras. * Typical output devices include monitors, printers, and speakers. * System resources must be assigned to computer components. System resources include IRQs, I/O port addresses, and DMAsCHAPTER 2 SAFETY WARNING TIPS | | 2.0 | | Introduction | |

| This chapter covers basic safety practices for the workplace, hardware and software tools, and the disposal of hazardous materials. Safety guidelines help protect individuals from accidents and injury and protect equipment from damage. Some of these guidelines are designed to protect the environment from contamination by discarded materials. Stay alert to situations that could result in injury or damage to equipment. Warning signs are designed to alert you to danger. Always watch for these signs and take the appropriate action according to the warning given.After completing this chapter, you will meet these objectives: * Explain the purpose of safe working conditions and procedures. * Identify tools and software used with personal computer components and their purposes. * Implement proper tool use. | | 2.1 | | Explain the purpose of safe working conditions and procedures | |

| Safe working conditions help to prevent injury to people and damage to computer equipment. A safe workspace is clean, organized, and properly lighted. Everyone must understand and follow safety procedures.Follow proper procedures for handling computer equipment to reduce the risk of personal injury, damage to property, and loss of data. Any damage or loss may result in claims for damage from the owner of the property and data.The proper disposal or recycling of hazardous computer components is a global issue. Make sure to follow regulations that govern how to dispose of specific items. Organizations that violate these regulations can be fined or face expensive legal battles.After completing this section, you will meet these objectives: * Identify safety procedures and potential hazards for users and technicians. * Identify safety procedures to protect equipment from damage and data from loss. * Identify safety procedures to protect the environment from contamination. | | 2.1.1 | | Identify safety procedures and potential hazards for users and technicians | |

| General Safety GuidelinesFollow the basic safety guidelines to prevent cuts, burns, electrical shock, and damage to eyesight. As is best practice, make sure that a fire extinguisher and first-aid kit are available in case of fire or injury. Poorly placed or unsecured cables usually cause tripping hazards in a network installation. Cables should be installed in conduit or cable trays to prevent hazards to users. Figure 1 shows a list of general safety guidelines. Electrical Safety GuidelinesFollow electrical safety guidelines to prevent electrical fires, injuries, and fatalities in the home and the workplace. Power supplies and monitors contain very high voltage. Only experienced technicians should attempt to repair power supplies and monitors, while most users should simply replace them. Do not wear the antistatic wrist strap when repairing power supplies or monitors. Some printer parts may become very hot when in use, and other parts may contain very high voltages. Make sure that the printer has had time to cool before making the repair. Check the printer manual for locations of various components that may contain high voltages. Some components may retain high voltages even after the printer is turned off. Electrical devices have certain power requirements. For example, AC adapters are manufactured for specific laptops. Exchanging power cords with a different type of laptop or device may cause damage to both the AC adapter and the laptop. Fire Safety GuidelinesFollow fire safety guidelines to protect lives, structures, and equipment. To avoid an electrical shock, and to prevent damage to the computer, turn off and unplug the computer before beginning a repair. Fire can spread rapidly and be very costly. Proper use of a fire extinguisher can prevent a small fire from getting out of control. When working with computer components, always consider the possibility of an accidental fire and know how to react. You should be alert for odors emitting from computers and electronic devices. When electronic components overheat or short out, they will emit a burning odor. If there is a fire, you should follow these safety procedures: * Never fight a fire that is out of control or not contained. * Always have a planned fire escape route before beginning any work. * Get out of the building quickly. * Contact emergency services for help. * Be sure to locate and read the instructions on the fire extinguishers in your workplace before you have to use them. Safety training may be available in your organization.In the United States, there are four classifications for fire extinguishers. A different letter, color, and shape identify each fire extinguisher classification, as shown in Figure 2. Each type of fire extinguisher has specific chemicals to fight different types of fires: Class A – Paper, wood, plastics, cardboardClass B – Gasoline, kerosene, organic solventsClass C – Electrical equipmentClass D – Combustible metalsWhat types of fire extinguisher classifications are there in your country? It is important to know how to use a fire extinguisher. Use the memory aid P-A-S-S to help you remember the basic rules of fire extinguisher operation: P - Pull the pin.A - Aim at the base of the fire, not at the flames.S - Squeeze the lever.S - Sweep the nozzle from side to side. | | 2.1.2 | | Identify safety procedures to protect equipment from damage and data from loss | |

| Electrostatic discharge (ESD), harsh climates, and poor-quality sources of electricity can cause damage to computer equipment. Follow proper handling guidelines, be aware of environmental issues, and use equipment that stabilizes power to prevent equipment damage and data loss.ESD
Static electricity is the buildup of an electric charge resting on a surface. This buildup may jump to a component and cause damage. This is known as electrostatic discharge (ESD). ESD can be destructive to the electronics in a computer system.At least 3,000 volts of static electricity must build up before a person can feel ESD. For example, static electricity can build up on you as you walk across a carpeted floor. When you touch another person, you both receive a shock. If the discharge causes pain or makes a noise, the charge was probably above 10,000 volts. By comparison, less than 30 volts of static electricity can damage a computer component.ESD Protection Recommendations
ESD can cause permanent damage to electrical components. Follow these recommendations to help prevent ESD damage: * Keep all components in antistatic bags until you are ready to install them. * Use grounded mats on workbenches. * Use grounded floor mats in work areas. * Use antistatic wrist straps when working on computers.EMI
Electromagnetic Interference (EMI) is the intrusion of outside electromagnetic signals in a transmission media, such as copper cabling. In a network environment, EMI distorts the signals so that the receiving devices have difficulty interpreting them.EMI does not always come from expected sources such as cellular phones. Other types of electric equipment can emit a silent, invisible electromagnetic field that can extend for more than a mile.As shown in Figure 1, there are many sources of EMI: * Any source designed to generate electromagnetic energy * Man-made sources like power lines or motors * Natural events such as electrical storms or solar and interstellar radiationsWireless networks are affected by Radio Frequency Interference (RFI). RFI is the interference caused by radio transmitters and other devices transmitting in the same frequency. For example, a cordless telephone can cause problems with a wireless network when both devices use the same frequency. Microwaves can also cause interference when positioned in close proximity to wireless networking devices.Climate
Climate affects computer equipment in a variety of ways: * If the environment temperature is too high, equipment can overheat. * If the humidity level is too low, the chance of ESD increases. * If the humidity level is too high, equipment can suffer from moisture damage.Figure 2 shows how environmental conditions increase or decrease the risk of ESD.Power Fluctuation Types
Voltage is the force that moves electrons through a circuit. The movement of electrons is called current. Computer circuits need voltage and current to operate electronic components. When the voltage in a computer is not accurate or steady, computer components may not operate correctly. Unsteady voltages are called power fluctuations.The following types of AC power fluctuations can cause data loss or hardware failure: * Blackout – Complete loss of AC power. A blown fuse, damaged transformer, or downed power line can cause a blackout. * Brownout – Reduced voltage level of AC power that lasts for a period of time. Brownouts occur when the power line voltage drops below 80% of the normal voltage level. Overloading electrical circuits can cause a brownout. * Noise – Interference from generators and lightning. Noise results in unclean power, which can cause errors in a computer system. * Spike – Sudden increase in voltage that lasts for a very short period and exceeds 100% of the normal voltage on a line. Spikes can be caused by lightning strikes, but can also occur when the electrical system comes back on after a blackout. * Power surge – Dramatic increase in voltage above the normal flow of electrical current. A power surge lasts for a few nanoseconds, or one-billionth of a second.Power Protection Devices
To help shield against power fluctuation issues, use protection devices to protect the data and computer equipment: * Surge suppressor – Helps protect against damage from surges and spikes. A surge suppressor diverts extra electrical voltage on the line to the ground. * Uninterruptible Power Supply (UPS) – Helps protect against potential electrical power problems by supplying electrical power to a computer or other device. The battery is constantly recharging while the UPS is in use. The UPS is able to supply a consistent quality of power when brownouts and blackouts occur. Many UPS devices are able to communicate directly with the operating system on a computer. This communication allows the UPS to safely shut down the computer and save data prior to the UPS losing all electrical power. * Standby Power Supply (SPS) – Helps protect against potential electrical power problems by providing a backup battery to supply power when the incoming voltage drops below the normal level. The battery is on standby during the normal operation. When the voltage decreases, the battery provides DC power to a power inverter, which converts it to AC power for the computer. This device is not as reliable as a UPS because of the time it takes to switch over to the battery. If the switching device fails, the battery will not be able to supply power to the computer. Figure 3 shows some examples of surge suppressors, UPS, and SPS devices.CAUTION: Never plug a printer into a UPS device. UPS manufacturers suggest never plugging a printer into a UPS for fear of overloading the UPS. | | 2.1.3 | | Identify safety procedures to protect the environment from contamination | |

| Computers and peripherals, as shown in Figure 1, contain materials that can be harmful to the environment. Hazardous materials are sometimes called toxic waste. These materials can contain high concentrations of heavy metals such as cadmium, lead, or mercury. The regulations for the disposal of hazardous materials vary according to state or country. Contact the local recycling or waste removal authorities in your community for information about disposal procedures and services.Material Safety and Data Sheet
A Material Safety and Data Sheet (MSDS) is a fact sheet that summarizes information about material identification, including hazardous ingredients that can affect personal health, fire hazards, and first aid requirements. In Figure 2, the MSDS sheet contains chemical reactivity and incompatibility information that includes spill, leak, and disposal procedures. It also includes protective measures for the safe handling and storage of materials.To determine if a material is classified as hazardous, consult the manufacturer's MSDS. In the U.S., the Occupational Safety and Health Administration (OSHA) requires that all hazardous materials must be accompanied by an MSDS when transferred to a new owner. The MSDS information included with products purchased for computer repairs or maintenance can be relevant to computer technicians. OSHA also requires that employees be informed about the materials that they are working with and be provided with material safety information. In the United Kingdom, Chemicals Hazard Information and Packaging for Supply Regulations 2002 (CHIP3) oversees the handling of hazardous materials. CHIP3 requires chemical suppliers to safely package and transport dangerous chemicals and to include a data sheet with the product.NOTE: The MSDS is valuable in determining how to dispose of any potentially hazardous materials in the safest manner. Always check local regulations concerning acceptable disposal methods before disposing of any electronic equipment.Which organization governs the use of hazardous chemicals in your country? Are MSDS sheets mandatory?The MSDS contains valuable information: * The name of the material * The physical properties of the material * Any hazardous ingredients contained in the material * Reactivity data, such as fire and explosion data * Procedures for spills or leaks * Special precautions * Health hazards * Special protection requirementsComputers and other computing devices are eventually discarded because of one of the following reasons: * Parts or components begin to fail more frequently as the device ages. * The computer becomes obsolete for the application for which it was originally intended. * Newer models have improved features.Before discarding a computer or any of its components, it is crucial to consider safe disposal of each separate component.Proper Disposal of Batteries
Batteries often contain rare earth metals that can be harmful to the environment. Batteries from portable computer systems may contain lead, cadmium, lithium, alkaline manganese, and mercury. These metals do not decay and will remain in the environment for many years. Mercury is commonly used in the manufacturing of batteries and is extremely toxic and harmful to humans.Recycling batteries should be a standard practice for a technician. All batteries, including lithium-ion, nickel-cadmium, nickel-metal hydride, and lead-acid are subject to disposal procedures that comply with local environmental regulations.Proper Disposal of Monitors or CRTs
Handle monitors and CRTs with care. Extremely high voltage can be stored in monitors and CRTs, even after being disconnected from a power source. CRTs contain glass, metal, plastics, lead, barium, and rare earth metals. According to the U.S. Environmental Protection Agency (EPA), CRTs may contain approximately 4 lbs (1.8 kg) of lead. Monitors must be disposed of in compliance with environmental regulations.Proper Disposal of Toner Kits, Cartridges, and Developers
Used printer toner kits and printer cartridges must be disposed of properly or recycled. Some toner cartridge suppliers and manufacturers will take empty cartridges for refilling. There are also companies that specialize in refilling empty cartridges. Kits to refill inkjet printer cartridges are available but are not recommended, because the ink may leak into the printer, causing irreversible damage. This can be especially costly because using refilled inkjet cartridges may also void the inkjet printer warranty.Proper Disposal of Chemical Solvents and Aerosol Cans
Contact the local sanitation company to learn how and where to dispose of the chemicals and solvents used to clean computers. Never dump chemicals or solvents down a sink or dispose of them in any drain that connects to public sewers.The cans or bottles that contain solvents and other cleaning supplies must be handled carefully. Make sure that they are identified and treated as special hazardous waste. For example, some aerosol cans may explode when exposed to heat if the contents are not completely used. | | 2.2 | | Identify tools and software used with personal computer components and their purposes | |

| For every job there is the right tool. Make sure that you are familiar with the correct use of each tool and that the right tool is used for the current task. Skilled use of tools and software makes the job less difficult and ensures that tasks are performed properly and safely.Software tools are available that help diagnose problems. Use these tools to determine which computer device is not functioning correctly.A technician must document all repairs and computer problems. The documentation can then be used as a reference for future problems or for other technicians who may not have encountered the problem before. The documents may be paper-based, but electronic forms are preferred because they can be easily searched for specific problems.After completing this section, you will meet these objectives: * Identify hardware tools and their purpose. * Identify software tools and their purpose. * Identify organizational tools and their purpose. | | 2.2.1 | | Identify hardware tools and their purpose | |

| A toolkit should contain all of the tools necessary to complete hardware repairs. As you gain experience, you will learn which tools to have available for different types of jobs. Hardware tools are grouped into these four categories: * ESD tools * Hand tools * Cleaning tools * Diagnostic toolsESD Tools
There are two ESD tools: the antistatic wrist strap and the antistatic mat. The antistatic wrist strap protects computer equipment when grounded to a computer chassis. The antistatic mat protects computer equipment by preventing static electricity from accumulating on the hardware or on the technician. Click each of the items in Figure 1 for more information on ESD tools.Hand Tools
Most tools used in the computer assembly process are small hand tools. They are available individually or as part of a computer repair toolkit. Toolkits range widely in size, quality, and price. Click each of the items in Figure 2 for more information on hand tools.Cleaning Tools
Having the appropriate cleaning tools is essential when maintaining or repairing computers. Using these tools ensures that computer components are not damaged during cleaning. Click each of the items in Figure 3 for more information on cleaning tools.Diagnostic Tools
A digital multimeter and a loopback adapter are used to test hardware. Click each of the items in Figure 4 for more information on diagnostic tools. | |

2.2.2 | | Identify software tools and their purpose | |

| A technician must be able to use a range of software tools to help diagnose problems, maintain hardware, and protect the data stored on a computer.Disk Management Tools
You must be able to identify which software to use in different situations. Disk management tools help detect and correct disk errors, prepare a disk for data storage, and remove unwanted files.Click each of the buttons in Figure 1 to see screen shots of the following disk management tools: * Fdisk or Disk Management – Creates and deletes partitions on a hard drive * Format – Prepares a hard drive to store information * Scandisk or Chkdsk – Checks the integrity of files and folders on a hard drive by scanning the file system. These tools may also check the disk surface for physical errors * Defrag – Optimizes space on a hard drive to allow faster access to programs and data * Disk Cleanup – Clears space on a hard drive by searching for files that can be safely deleted * Disk Management – Initializes disks, creates partitions, and formats partitions * System File Checker (SFC) – Scans the operating system critical files and replaces any files that are corruptedUse the Windows XP boot disk for troubleshooting and repairing corrupted files. The Windows XP boot disk is designed to repair Windows system files, restore damaged or lost files, and reinstall the operating system. Third-party software tools are available to assist in troubleshooting problems.Protection Software Tools
Each year, viruses, spyware, and other types of malicious attacks infect millions of computers. These attacks can damage an operating system, application, and data. Computers that have been infected may even have problems with hardware performance or component failure.To protect data and the integrity of the operating system and hardware, use software designed to guard against attacks and to remove malicious programs.Various types of software are used to protect hardware and data. Click each of the buttons in Figure 2 to see screen shots of these protection software tools: * Windows XP Security Center – Checks the status of essential security settings. The Security Center continuously checks to make sure that the software firewall and antivirus programs are running. It also ensures that automatic updates are set to download and install automatically. * Antivirus program – Protects against virus attacks. * Spyware remover – Protects against software that sends information about web surfing habits to an attacker. Spyware can be installed without the knowledge or consent of the user. * Firewall program – Runs continuously to protect against unauthorized communications to and from your computer. | | 2.2.3 | | Identify organizational tools and their purpose | |

| It is important that a technician document all services and repairs. These documents need to be stored centrally and made available to all other technicians. The documentation can then be used as reference material for similar problems that are encountered in the future. Good customer service includes providing the customer with a detailed description of the problem and the solution.Personal Reference Tools
Personal reference tools include troubleshooting guides, manufacturer manuals, quick reference guides, and repair journals. In addition to an invoice, a technician keeps a journal of upgrades and repairs. The documentation in the journal should include descriptions of the problem, possible solutions that have been attempted, and the steps taken to repair the problem. Be sure to note any configuration changes made to the equipment and any replacement parts used in the repair. This documentation will be valuable when you encounter similar situations in the future. * Notes – Make notes as you go through the investigation and repair process. Refer to these notes to avoid repeating previous steps and to determine what steps to take next. * Journal – Document the upgrades and repairs that you perform. The documentation should include descriptions of the problem, possible solutions that have been tried in order to correct the problem, and the steps taken to repair the problem. Be sure to note any configuration changes made to the equipment and any replacement parts used in the repair. Your journal, along with your notes, can be valuable when you encounter similar situations in the future. * History of repairs – Make a detailed list of problems and repairs, including the date, replacement parts, and customer information. The history allows a technician to determine what work has been performed on a computer in the past.Internet Reference Tools
The Internet is an excellent source of information about specific hardware problems and possible solutions: * Internet search engines * News groups * Manufacturer FAQs * Online computer manuals * Online forums and chat * Technical websitesFigure 1 shows an example of a technical website.Miscellaneous Tools
With experience, you will discover many additional items to add to the toolkit. Figure 2 shows how a roll of masking tape can be used to label parts that have been removed from a computer when a parts organizer is not available.A working computer is also a valuable resource to take with you on computer repairs in the field. A working computer can be used to research information, download tools or drivers, or communicate with other technicians.Figure 3 shows the types of computer replacement parts to include in a toolkit. Make sure that the parts are in good working order before you use them. Using known good components to replace possible bad ones in computers will help you quickly determine which component may not be working properly. | | 2.3 | | Implement proper tool use | |

| Safety in the workplace is everyone's responsibility. You are much less likely to injure yourself or damage components when using the proper tool for the job.Before cleaning or repairing equipment, check to make sure that your tools are in good condition. Clean, repair, or replace any items that are not functioning adequately.After completing this section, you will meet these objectives: * Demonstrate proper use of an antistatic wrist strap. * Demonstrate proper use of an antistatic mat. * Demonstrate proper use of various hand tools. * Demonstrate proper use of cleaning materials. | | 2.3.1 | | Demonstrate proper use of an antistatic wrist strap | |

| As discussed previously, an example of ESD is the small shock that you receive when you walk across a room with carpet and touch a doorknob. Although the small shock is harmless to you, the same electrical charge passing from you to a computer can damage its components. Wearing an antistatic wrist strap can prevent ESD damage to computer components.The purpose of an antistatic wrist strap is to equalize the electrical charge between you and the equipment. The antistatic wrist strap is a conductor that connects your body to the equipment that you are working on. When static electricity builds up in your body, the connection made by the wrist strap to the equipment, or ground, channels the electricity through the wire that connects the strap.As shown in Figure 1, the wrist strap has two parts and is easy to wear: 1. Wrap the strap around your wrist and secure it using the snap or Velcro. The metal on the back of the wrist strap must remain in contact with your skin at all times. 2. Snap the connector on the end of the wire to the wrist strap, and connect the other end either to the equipment or to the same grounding point that the antistatic mat is connected to. The metal skeleton of the case is a good place to connect the wire. When connecting the wire to equipment that you are working on, choose an unpainted metal surface. A painted surface does not conduct the electricity as well as unpainted metal.NOTE: Attach the wire on the same side of the equipment as the arm wearing the antistatic wrist strap. This will help to keep the wire out of the way while you are working.Although wearing a wrist strap will help to prevent ESD, you can further reduce the risks by not wearing clothing made of silk, polyester, or wool. These fabrics are more likely to generate a static charge.NOTE: Technicians should roll up their sleeves, remove scarfs or ties, and tuck in their shirts to prevent interference from clothing. Ensure that earrings, necklaces, and other loose jewelry are properly secured.CAUTION: Never wear an antistatic wrist strap if you are repairing a monitor or a power supply unit. | | 2.3.2 | | Demonstrate proper use of an antistatic mat | |

| You may not always have the option to work on a computer in a properly equipped workspace. If you can control the environment, try to set up your workspace away from carpeted areas. Carpets can cause the buildup of electrostatic charges. If you cannot avoid the carpeting, ground yourself to the unpainted portion of the case of the computer on which you are working before touching any components.Antistatic Mat
An antistatic mat is slightly conductive. It works by drawing static electricity away from a component and transferring it safely from equipment to a grounding point, as shown in Figure 1: 1. Lay the mat on the workspace next to or under the computer case. 2. Clip the mat to the case to provide a grounded surface on which you can place parts as you remove them from the system.Reducing the potential for ESD reduces the likelihood of damage to delicate circuits or components.NOTE: Always handle components by the edges.Workbench
When you are working at a workbench, ground the workbench and the antistatic floor mat. By standing on the mat and wearing the wrist strap, your body has the same charge as the equipment and reduces the probability of ESD. | |

2.3.3 | | Demonstrate proper use of various hand tools | |

| A technician needs to be able to properly use each tool in the toolkit. This topic covers many of the various hand tools used when repairing computers.Screws
Match each screw with the proper screwdriver. Place the tip of the screwdriver on the head of the screw. Turn the screwdriver clockwise to tighten the screw and counterclockwise to loosen the screw, as shown in Figure 1.Screws can become stripped if you over-tighten them with a screwdriver. A stripped screw, shown in Figure 2, may get stuck in the screw hole, or it may not tighten firmly. Discard stripped screws.Flat Head Screwdriver
As shown in Figure 3, use a flat head screwdriver when you are working with a slotted screw. Do not use a flat head screwdriver to remove a Phillips head screw. Never use a screwdriver as a pry bar. If you cannot remove a component, check to see if there is a clip or latch that is securing the component in place.CAUTION: If excessive force is needed to remove or add a component, something is probably wrong. Take a second look to make sure that you have not missed a screw or a locking clip that is holding the component in place. Refer to the device manual or diagram for additional information.Phillips Head Screwdriver
As shown in Figure 4, use a Phillips head screwdriver with crosshead screws. Do not use this type of screwdriver to puncture anything. This will damage the head of the screwdriver.Hex Driver
As shown in Figure 5, use a hex driver to loosen and tighten bolts that have a hexagonal (six-sided) head. Hex bolts should not be over-tightened because the threads of the bolts can be stripped. Do not use a hex driver that is too large for the bolt that you are using.CAUTION: Some tools are magnetized. When working around electronic devices, be sure that the tools you are using have not been magnetized. Magnetic fields can be harmful to data stored on magnetic media. Test your tool by touching the tool with a screw. If the screw is attracted to the tool, do not use the tool.Part Retriever, Needle-Nose Pliers, or Tweezers
As shown in Figure 6, the part retriever, needle-nose pliers, and tweezers can be used to place and retrieve parts that may be hard to reach with your fingers. Do not scratch or hit any components when using these tools.CAUTION: Pencils should not be used inside the computer to change the setting of switches or to pry off jumpers. The pencil lead can act as a conductor and may damage the computer components. | | 2.3.4 | | Demonstrate proper use of cleaning materials | |

| Keeping computers clean inside and out is a vital part of a maintenance program. Dirt can cause problems with the physical operation of fans, buttons, and other mechanical components. Figure 1 shows severe dust buildup on computer components. On electrical components, an excessive buildup of dust will act like an insulator and trap the heat. This insulation will impair the ability of heat sinks and cooling fans to keep components cool, causing chips and circuits to overheat and fail.CAUTION: When compressed air is used to clean inside the computer, the air should be blown around the components with a minimum distance of four inches from the nozzle. The power supply and the fan should be cleaned from the back of the case.CAUTION: Before cleaning any device, turn it off and unplug the device from the power source.Computer Cases and Monitors
Clean computer cases and the outside of monitors with a mild cleaning solution on a damp, lint-free cloth. Mix one drop of dishwashing liquid with four ounces of water to create the cleaning solution. If any water drips inside the case, allow enough time for the liquid to dry before powering on the computer.LCD Screens
Do not use ammoniated glass cleaners or any other solution on an LCD screen, unless the cleaner is specifically designed for the purpose. Harsh chemicals will damage the coating on the screen. There is no glass protecting these screens, so be gentle when cleaning them and do not press firmly on the screen.CRT Screens
To clean the screens of CRT monitors, dampen a soft, clean, lint-free cloth with distilled water and wipe the screen from top to bottom. Then use a soft, dry cloth to wipe the screen and remove any streaking after you have cleaned the monitor.Clean dusty components with a can of compressed air. Compressed air does not cause electrostatic buildup on components. Make sure that you are in a well-ventilated area before blowing the dust out of the computer. A best practice is to wear a dust mask to make sure that you do not breathe in the dust particles.Blow out the dust using short bursts from the can. Never tip the can or use the compressed air can upside down. Do not allow the fan blades to spin from the force of the compressed air. Hold the fan in place. Fan motors can be ruined from spinning when the motor is not turned on.Component Contacts
Clean the contacts on components with isopropyl alcohol. Do not use rubbing alcohol. Rubbing alcohol contains impurities that can damage contacts. Make sure that the contacts do not collect any lint from the cloth or cotton swab. Blow any lint off the contacts with compressed air before reinstallation.Keyboard
Clean a desktop keyboard with compressed air or a small, hand-held vacuum cleaner with a brush attachment.CAUTION: Never use a standard vacuum cleaner inside a computer case. The plastic parts of the vacuum cleaner can build up static electricity and discharge to the components. Use only a vacuum approved for electronic components.Mouse
Use glass cleaner and a soft cloth to clean the outside of the mouse. Do not spray glass cleaner directly on the mouse. If cleaning a ball mouse, you can remove the ball and clean it with glass cleaner and a soft cloth. Wipe the rollers clean inside the mouse with the same cloth. Do not spray any liquids inside the mouse.The chart in Figure 2 indicates the computer items that you should clean and the cleaning materials that you should use in each case. | |

2.4 | | Summary | |

| This chapter discussed safe lab procedures, correct tool usage, and the proper disposal of computer components and supplies. You have familiarized yourself in the lab with many of the tools used to build, service, and clean computer and electronic components. You have also learned the importance of organizational tools and how these tools help you work more efficiently.The following are some of the important concepts to remember from this chapter: * Work in a safe manner to protect both users and equipment. * Follow all safety guidelines to prevent injuries to yourself and to others. * Know how to protect equipment from ESD damage. * Know about and be able to prevent power issues that can cause equipment damage or data loss. * Know which products and supplies require special disposal procedures. * Familiarize yourself with MSDS sheets for both safety issues and disposal restrictions to help protect the environment. * Be able to use the correct tools for the task. * Know how to clean components safely. * Use organizational tools during computer repairsCHAPTER 3 COMPUTER ASSEMBLY 3.0 | | Introduction | | | Assembling computers is a large part of a technician's job. As a technician, you will need to work in a logical, methodical manner when working with computer components. As with any learned trade, computer assembly skills will improve dramatically with practice.After completing this chapter, you will meet these objectives: * Open the case. * Install the power supply. * Attach the components to the motherboard and install the motherboard. * Install internal drives. * Install drives in external bays. * Install adapter cards. * Connect all internal cables. * Re-attach the side panels and connect external cables to the computer. * Boot the computer for the first time. | | 3.1 | | Open the case | | | Computer cases are produced in a variety of form factors. Form factors refer to the size and shape of the case.Prepare the workspace before opening the computer case. There should be adequate lighting, good ventilation, and a comfortable room temperature. The workbench or table should be accessible from all sides. Avoid cluttering the surface of the workbench or table with tools and computer components. An antistatic mat on the table will help prevent physical and ESD damage to equipment. Small containers can be used to hold small screws and other parts as they are being removed.There are different methods for opening cases. To learn how to open a particular computer case, consult the user manual or manufacturer's website. Most computer cases are opened in one of the following ways: * The computer case cover can be removed as one piece. * The top and side panels of the case can be removed. * The top of the case may need to be removed before the side panels can be removed. | | 3.2 | | Install the power supply | | | A technician may be required to replace or install a power supply. Most power supplies can only fit one way in the computer case. There are usually three or four screws that attach the power supply to the case. Power supplies have fans that can vibrate and loosen screws that are not secured. When installing a power supply, make sure that all of the screws are used and that they are properly tightened.These are the power supply installation steps: 1. Insert the power supply into the case. 2. Align the holes in the power supply with the holes in the case. 3. Secure the power supply to the case using the proper screws. 3.3 | | Attach the components to the motherboard and install the motherboard | | | This section details the steps to install components on the motherboard and then install the motherboard into the computer case.After completing this section, you will meet these objectives: * Install a CPU and a heat sink/fan assembly. * Install the RAM. * Install the motherboard. | | 3.3.1 | | Install a CPU and a heat sink/fan assembly | | | The CPU and the heat sink/fan assembly may be installed on the motherboard before the motherboard is placed in the computer case.CPU
Figure 1 shows a close-up view of the CPU and the motherboard. The CPU and motherboard are sensitive to electrostatic discharge. When handling a CPU and motherboard, make sure that you place them on a grounded antistatic mat. You should wear an antistatic wrist strap while working with these components.CAUTION: When handling a CPU, do not touch the CPU contacts at any time.The CPU is secured to the socket on the motherboard with a locking assembly. The CPU sockets today are ZIF sockets. You should be familiar with the locking assembly before attempting to install a CPU into the socket on the motherboard.Thermal compound helps to conduct heat away from the CPU. Figure 2 shows thermal compound being applied to the CPU.When you are installing a used CPU, clean the CPU and the base of the heat sink with isopropyl alcohol. Doing this removes all traces of old thermal compound. The surfaces are now ready for a new layer of thermal compound. Follow all manufacturer recommendations about applying the thermal compound.Heat Sink/Fan Assembly
Figure 3 shows the heat sink/fan assembly. It is a two-part cooling device. The heat sink draws heat away from the CPU. The fan moves the heat away from the heat sink. The heat sink/fan assembly usually has a 3-pin power connector.Figure 4 shows the connector and the motherboard header for the heat sink/fan assembly.Follow these instructions for CPU and heat sink/fan assembly installation: 1. Align the CPU so that the Connection 1 indicator is lined up with Pin 1 on the CPU socket. Doing this ensures that the orientation notches on the CPU are aligned with the orientation keys on the CPU socket. 2. Place the CPU gently into the socket. 3. Close the CPU load plate and secure it in place by closing the load lever and moving it under the load lever retention tab. 4. Apply a small amount of thermal compound to the CPU and spread it evenly. Follow the application instructions provided by the manufacturer. 5. Align the heat sink/fan assembly retainers with the holes on the motherboard. 6. Place the heat sink/fan assembly onto the CPU socket, being careful not to pinch the CPU fan wires. 7. Tighten the heat sink/fan assembly retainers to secure the assembly in place. 8. Connect the heat sink/fan assembly power cable to the header on the motherboard. | | | | | | 3.3.2 | | Install the RAM | |

| Like the CPU and the heat sink/fan assembly, RAM is installed in the motherboard before the motherboard is secured in the computer case. Before you install a memory module, consult the motherboard documentation or website of the manufacturer to ensure that the RAM is compatible with the motherboard.RAM provides temporary data storage for the CPU while the computer is operating. RAM is volatile memory, which means that its contents are lost when the computer is shut down. Typically, more RAM will enhance the performance of your computer.Follow these steps for RAM installation: 1. Align the notches on the RAM module to the keys in the slot and press down until the side tabs click into place. 2. Make sure that the side tabs have locked the RAM module. Visually check for exposed contacts.Repeat these steps for additional RAM modules. | | 3.3.3 | | Install the motherboard | |

| The motherboard is now ready to install in the computer case. Plastic and metal standoffs are used to mount the motherboard and to prevent it from touching the metal portions of the case. You should install only the standoffs that align with the holes in the motherboard. Installing any additional standoffs may prevent the motherboard from being seated properly in the computer case.Follow these steps for motherboard installation: 1. Install standoffs in the computer case. 2. Align the I/O connectors on the back of the motherboard with the openings in the back of the case. 3. Align the screw holes of the motherboard with the standoffs. 4. Insert all of the motherboard screws. 5. Tighten all of the motherboard screws. 3.4 | | Install internal drives | | | Drives that are installed in internal bays are called internal drives. A hard disk drive (HDD) is an example of an internal drive.Follow these steps for HDD installation: 1. Position the HDD so that it aligns with the 3.5-inch drive bay. 2. Insert the HDD into the drive bay so that the screw holes in the drive line up with the screw holes in the case. 3. Secure the HDD to the case using the proper screws. | | | | Optional ActivityVirtual Desktop: Internal Drives
System requirements for the virtual desktop include a minimum of 512 MB RAM and Windows 2000 or Windows XP operating system.
Complete the hard drive installation in the virtual desktop internal drive layer. | | | | | | | 3.5 | | Install drives in external bays | |

| Drives, such as optical drives and floppy drives, are installed in drive bays that are accessed from the front of the case. Optical drives and floppy drives store data on removable media. Drives in external bays allow access to the media without opening the case.After completing this section, you will meet these objectives: * Install the optical drive. * Install the floppy drive. | | 3.5.1 | | Install the optical drive | |

| An optical drive is a storage device that reads and writes information to CDs and DVDs. A Molex power connector provides the optical drive with power from the power supply. A PATA cable connects the optical drive to the motherboard.Follow these steps for optical drive installation: 1. Position the optical drive so that it aligns with the 5.25-inch drive bay. 2. Insert the optical drive into the drive bay so that the optical drive screw holes align with the screw holes in the case. 3. Secure the optical drive to the case using the proper screws | | 3.5.2 | | Install the floppy drive | |

| A floppy disk drive (FDD) is a storage device that reads and writes information to a floppy disk. A Berg power connector provides the FDD with power from the power supply. A floppy data cable connects the FDD to the motherboard.A floppy disk drive fits into the 3.5-inch bay on the front of the computer case.Follow these steps for FDD installation: 1. Position the FDD so that it aligns with the 3.5-inch drive bay. 2. Insert the FDD into the drive bay so that the FDD screw holes align with the screw holes in the case. 3. Secure the FDD to the case using the proper screws. | | | | Optional ActivityVirtual Desktop: Drives in External Bays
System requirements for the virtual desktop include a minimum of 512 MB RAM and Windows 2000 or Windows XP operating system.
Complete the optical and floppy drive installation in the virtual desktop drives in external bays layer.

LabInstall the Drives
Install the hard disk drive, the optical drive, and the floppy drive. | | | | | 3.6 | | Install adapter cards | |

| Adapter cards are installed to add functionality to a computer. Adapter cards must be compatible with the expansion slot. This section focuses on the installation of three types of adapter cards: * PCIe x1 NIC * PCI wireless NIC * PCIe x16 video adapter cardAfter completing this section, you will meet these objectives: * Install the NIC. * Install the wireless NIC. * Install the video adapter card. | | 3.6.1 | | Install the NIC | |

| A NIC enables a computer to connect to a network. NICs use PCI and PCIe expansion slots on the motherboard.Follow these steps for NIC installation: 1. Align the NIC to the appropriate expansion slot on the motherboard. 2. Press down gently on the NIC until the card is fully seated. 3. Secure the NIC PC mounting bracket to the case with the appropriate screw. | | 3.6.2 | | Install the wireless NIC | |

| A wireless NIC enables a computer to connect to a wireless network. Wireless NICs use PCI and PCIe expansion slots on the motherboard. Some wireless NICs are installed externally with a USB connector.Follow these steps for wireless NIC installation: 1. Align the wireless NIC to the appropriate expansion slot on the motherboard. 2. Press down gently on the wireless NIC until the card is fully seated. 3. Secure the wireless NIC PC mounting bracket to the case with the appropriate screw. | | 3.6.3 | | Install the video adapter card | |

| A video adapter card is the interface between a computer and a display monitor. An upgraded video adapter card can provide better graphic capabilities for games and graphic programs. Video adapter cards use PCI, AGP, and PCIe expansion slots on the motherboard.Follow these steps for video adapter card installation: 1. Align the video adapter card to the appropriate expansion slot on the motherboard. 2. Press down gently on the video adapter card until the card is fully seated. 3. Secure the video adapter card PC mounting bracket to the case with the appropriate screw. | | | | Optional ActivityVirtual Desktop: Adapter Cards
System requirements for the virtual desktop include a minimum of 512 MB RAM and Windows 2000 or Windows XP operating system.
Complete the NIC, wireless NIC, and video adapter card installation in the virtual desktop adapter card layer.

LabInstall Adapter Cards
Install a NIC, a wireless NIC, and a video adapter card. | | | | | 3.7 | | Connect all internal cables | |

| Power cables are used to distribute electricity from the power supply to the motherboard and other components. Data cables transmit data between the motherboard and storage devices, such as hard drives. Additional cables connect the buttons and link lights on the front of the computer case to the motherboard.After completing this section, you will meet these objectives: * Connect the power cables. * Connect the data cables. | | 3.7.1 | | Connect the power cables | |

| Motherboard Power Connections
Just like other components, motherboards require power to operate. The Advanced Technology Extended (ATX) main power connector will have either 20 or 24 pins. The power supply may also have a 4-pin or 6-pin Auxiliary (AUX) power connector that connects to the motherboard. A 20-pin connector will work in a motherboard with a 24-pin socket.Follow these steps for motherboard power cable installation: 1. Align the 20-pin ATX power connector to the socket on the motherboard. [Figure 1] 2. Gently press down on the connector until the clip clicks into place. 3. Align the 4-pin AUX power connector to the socket on the motherboard. [Figure 2] 4. Gently press down on the connector until the clip clicks into place.SATA Power Connectors
SATA power connectors use a 15-pin connector. SATA power connectors are used to connect to hard disk drives, optical drives, or any devices that have a SATA power socket.Molex Power Connectors
Hard disk drives and optical drives that do not have SATA power sockets use a Molex power connector.CAUTION: Do not use a Molex connector and a SATA power connector on the same drive at the same time.Berg Power Connectors
The 4-pin Berg power connector supplies power to a floppy drive.Follow these steps for power connector installation: 1. Plug the SATA power connector into the HDD. [Figure 3] 2. Plug the Molex power connector into the optical drive. [Figure 4] 3. Plug the 4-pin Berg power connector into the FDD. [Figure 5] 4. Connect the 3-pin fan power connector into the appropriate fan header on the motherboard, according to the motherboard manual. [Figure 6] 5. Plug the additional cables from the case into the appropriate connectors according to the motherboard manual. | | 3.7.2 | | Connect the data cables | |

| Drives connect to the motherboard using data cables. The drive being connected determines the type of data cable used. The types of data cables are PATA, SATA, and floppy disk.PATA Data Cables
The PATA cable is sometimes called a ribbon cable because it is wide and flat. The PATA cable can have either 40 or 80 conductors. A PATA cable usually has three 40-pin connectors. One connector at the end of the cable connects to the motherboard. The other two connectors connect to drives. If multiple hard drives are installed, the master drive connects to the end connector. The slave drive connects to the middle connector.A stripe on the data cable denotes the location of pin 1. Plug the PATA cable into the drive with the pin 1 indicator on the cable aligned to the pin 1 indicator on the drive connector. The pin 1 indicator on the drive connector is usually closest to the power connector on the drive. Many motherboards have two PATA drive controllers, providing support for a maximum of four PATA drives.SATA Data Cables
The SATA data cable has a 7-pin connector. One end of the cable is connected to the motherboard. The other end is connected to any drive that has a SATA data connector.Floppy Data Cables
The floppy drive data cable has a 34-pin connector. Like the PATA data cable, the floppy drive data cable has a stripe to denote the location of pin 1. A floppy drive cable usually has three 34-pin connectors. One connector at the end of the cable connects to the motherboard. The other two connectors connect to drives. If multiple floppy drives are installed, the A: drive connects to the end connector. The B: drive connects to the middle connector.Plug the floppy drive data cable into the drive with the pin 1 indicator on the cable aligned to the pin 1 indicator on the drive connector. Motherboards have one floppy drive controller, providing support for a maximum of two floppy drives.NOTE: If pin 1 on the floppy drive data cable is not aligned with pin 1 on the drive connector, the floppy drive does not function. This misalignment does not damage the drive, but the drive activity light displays continuously. To fix this problem, turn off the computer and reconnect the data cable so that pin 1 on the cable and pin 1 on the connector are aligned. Reboot the computer.Follow these steps for data cable installation: 1. Plug the motherboard end of the PATA cable into the motherboard socket. [Figure 1] 2. Plug the connector at the far end of the PATA cable into the optical drive. [Figure 2] 3. Plug one end of the SATA cable into the motherboard socket. [Figure 3] 4. Plug the other end of the SATA cable into the HDD. [Figure 4] 5. Plug the motherboard end of the FDD cable into the motherboard socket. [Figure 5] 6. Plug the connector at the far end of the FDD cable into the floppy drive. [Figure 6] | | | | Optional ActivityVirtual Desktop: Internal Cables
System requirements for the virtual desktop include a minimum of 512 MB RAM and Windows 2000 or Windows XP operating system.
Complete the internal cable installation in the virtual desktop internal cable layer.

LabInstall Internal Cables
Install the internal power and data cables in the computer. | | | | | 3.8 | | Re-attach the side panels and connect external cables to the computer | |

| Now that all the internal components have been installed and connected to the motherboard and power supply, the side panels are re-attached to the computer case. The next step is to connect the cables for all computer peripherals and the power cable.After completing this section, you will meet these objectives: * Re-attach the side panels to the case. * Connect external cables to the computer. | | 3.8.1 | | Re-attach the side panels to the case | |

| Most computer cases have two panels, one on each side. Some computer cases have one three-sided cover that slides down over the case frame.When the cover is in place, make sure that it is secured at all screw locations. Some computer cases use screws that are inserted with a screwdriver. Other cases have knob-type screws that can be tightened by hand.If you are unsure about how to remove or replace the computer case, refer to the documentation or website of the manufacturer for more information.CAUTION: Handle case parts with care. Some computer case covers have sharp or jagged edges. | | 3.8.2 | | Connect external cables to the computer | |

| After the case panels have been re-attached, connect the cables to the back of the computer. Here are some common external cable connections: * Monitor * Keyboard * Mouse * USB * Ethernet * PowerWhen attaching cables, ensure that they are connected to the correct locations on the computer. For example, some mouse and keyboard cables use the same type of PS/2 connector.CAUTION: When attaching cables, never force a connection.NOTE: Plug in the power cable after you have connected all other cables.Follow these steps for external cable installation: 1. Attach the monitor cable to the video port. [Figure 1] 2. Secure the cable by tightening the screws on the connector. 3. Plug the keyboard cable into the PS/2 keyboard port. [Figure 2] 4. Plug the mouse cable into the PS/2 mouse port. [Figure 3] 5. Plug the USB cable into a USB port. [Figure 4] 6. Plug the network cable into the network port. [Figure 5] 7. Connect the wireless antenna to the antenna connector. [Figure 6] 8. Plug the power cable into the power supply. [Figure 7]Figure 8 shows all of the external cables plugged into the back of the computer. | | | | Optional ActivityVirtual Desktop: External Cables
System requirements for the virtual desktop include a minimum of 512 MB RAM and Windows 2000 or Windows XP operating system.
Complete the external cable installation in the virtual desktop external cable layer.

LabComplete the Computer Assembly
Install the side panels and the external cables on the computer. | | | | | 3.9 | | Boot the computer for the first time | |

| When the computer is booted, the basic input/output system (BIOS) performs a check on all of the internal components. This check is called a power-on self test (POST).After completing this section, you will meet these objectives: * Identify beep codes. * Describe BIOS setup. | | 3.9.1 | | Identify beep codes | |

| POST checks to see that all of the hardware in the computer is operating correctly. If a device is malfunctioning, an error or a beep code alerts the technician that there is a problem. Typically, a single beep denotes that the computer is functioning properly. If there is a hardware problem, the computer might emit a series of beeps. Each BIOS manufacturer uses different codes to indicate hardware problems. Figure 1 shows a sample chart of beep codes. The beep codes for your computer might be different. Consult the motherboard documentation to view beep codes for your computer. | | 3.9.2 | | Describe BIOS setup | |

| The BIOS contains a setup program used to configure settings for hardware devices. The configuration data is saved to a special memory chip called a Complementary Metal Oxide Semiconductor (CMOS), as shown in Figure 1. CMOS is maintained by the battery in the computer. If this battery dies, all BIOS setup configuration data will be lost. If this occurs, replace the battery and reconfigure the BIOS settings.To enter the BIOS setup program, you must press the proper key or key sequence during POST. Most computers use the DEL key. Your computer might use another key or combination of keys.Figure 2 shows an example of a BIOS setup program. Here are some common BIOS setup menu options: * Main – System time, date, HDD type, etc. * Advanced – Infrared port settings, parallel port settings, etc. * Security – Password settings to setup utility * Others – Low battery alarm, system beep, etc. * Boot – Boot order of the computer * Exit – Setup utility exit | | | | LabBoot the Computer
Boot the computer for the first time, explore the BIOS setup program, and change the boot order sequence. | | | | | 3.10 | | Summary | |

| This chapter detailed the steps used to assemble a computer and to boot the system for the first time. These are some important points to remember: * Computer cases come in a variety of sizes and configurations. Many of the components of the computer must match the form factor of the case. * The CPU is installed on the motherboard with a heat sink/fan assembly. * RAM is installed in RAM slots found on the motherboard. * Adapter cards are installed in PCI and PCIe expansion slots found on the motherboard. * Hard disk drives are installed in 3.5-inch drive bays located inside the case. * Optical drives are installed in 5.25-inch drive bays that can be accessed from outside the case. * Floppy drives are installed in 3.5-inch drive bays that can be accessed from outside the case. * Power supply cables are connected to all drives and the motherboard. * Internal data cables transfer data to all drives. * External cables connect peripheral devices to the computer. * Beep codes signify when hardware malfunctions. * The BIOS setup program is used to display information about the computer components and allows the user to change system settings.CHAPTER 4 COMPUTER MAINTENANCE AND TROUBLE SHOOTING | | 4.0 | | Introduction | |

| This chapter introduces preventive maintenance and the troubleshooting process. Preventive maintenance is a regular and systematic inspection, cleaning, and replacement of worn parts, materials, and systems. Preventive maintenance helps to prevent failure of parts, materials, and systems by ensuring that they are in good working condition. Troubleshooting is a systematic approach to locating the cause of a fault in a computer system. With fewer faults, there is less troubleshooting to do, thus saving an organization time and money.Troubleshooting is a learned skill. Not all troubleshooting processes are the same, and technicians tend to refine their own troubleshooting skills based on knowledge and personal experience. Use the guidelines in this chapter as a starting point to help develop your troubleshooting skills. Although each situation is different, the process described in this chapter will help you to determine your course of action when you are trying to solve a technical problem for a customer.After completing this chapter, you will meet these objectives: * Explain the purpose of preventive maintenance. * Identify the steps of the troubleshooting process 4.1 | | Explain the purpose of preventive maintenance | | | Preventive maintenance reduces the probability of hardware or software problems by systematically and periodically checking hardware and software to ensure proper operation.Hardware
Check the condition of cables, components, and peripherals. Clean components to reduce the likelihood of overheating. Repair or replace any components that show signs of abuse or excess wear. Use the tasks listed in Figure 1 as a guide to create a hardware maintenance program.What additional hardware maintenance tasks can you add to the list?Software
Verify that installed software is current. Follow the policies of the organization when installing security updates, operating system updates, and program updates. Many organizations do not allow updates until extensive testing has been completed. This testing is done to confirm that the update will not cause problems with the operating system and software. Use the tasks listed in Figure 2 as a guide to create a software maintenance schedule that fits the needs of your computer equipment.What other software maintenance tasks can you add to the list?Benefits
Be proactive in computer equipment maintenance and data protection. By performing regular maintenance routines, you can reduce potential hardware and software problems. Regular maintenance routines reduce computer downtime and repair costs.A preventive maintenance plan is developed based on the needs of the equipment. A computer exposed to a dusty environment, such as a construction site, needs more attention than equipment in an office environment. High-traffic networks, such as a school network, might require additional scanning and removal of malicious software or unwanted files. Document the routine maintenance tasks that must be performed on the computer equipment and the frequency of each task. This list of tasks can then be used to create a maintenance program.Some benefits of preventive maintenance are listed in Figure 3. Can you think of any other benefits that preventive maintenance provides? | | | | 4.2 | | Identify the steps of the troubleshooting process | |

| Troubleshooting requires an organized and logical approach to problems with computers and other components. A logical approach to troubleshooting allows you to eliminate variables in a systematic order. Asking the right questions, testing the right hardware, and examining the right data helps you understand the problem. This helps you form a proposed solution to try.Troubleshooting is a skill that you will refine over time. Each time you solve another problem, you will increase your troubleshooting skills by gaining more experience. You will learn how and when to combine, as well as skip, steps to reach a solution quickly. The troubleshooting process is a guideline that can be modified to fit your needs.In this section, you will learn an approach to problem solving that can be applied to both hardware and software. Many of the steps can also be applied to problem solving in other work-related areas.NOTE: The term customer, as used in this course, is any user that requires technical computer assistance.After completing this section, you will meet these objectives: * Explain the purpose of data protection. * Identify the problem. * Establish a theory of probable causes. * Test the theory to determine an exact cause. * Establish a plan of action to resolve the problem and implement the solution. * Verify full system functionality, and if applicable, implement preventive measures. * Document findings, actions and outcomes. | | 4.2.1 | | Explain the purpose of data protection | |

| Before you begin troubleshooting problems, always follow the necessary precautions to protect data on a computer. Some repairs, such as replacing a hard drive or reinstalling an operating system, might put the data on the computer at risk. Make sure that you do everything possible to prevent data loss while attempting repairs.CAUTION: Although data protection is not one of the six troubleshooting steps, you must protect data before beginning any work on a customer's computer. If your work results in data loss for the customer, you or your company could be held liable.Data Backup
A data backup is a copy of the data on a computer hard drive that is saved to media such as a CD, DVD, or tape drive. In an organization, backups are routinely done on a daily, weekly, and monthly basis.If you are unsure that a backup has been done, do not attempt any troubleshooting activities until you check with the customer. Here is a list of items to verify with the customer about data backups: * Date of the last backup * Contents of the backup * Data integrity of the backup * Availability of all backup media for a data restoreIf the customer does not have a current backup and you are not able to create one, you should ask the customer to sign a liability release form. A liability release form should contain at least the following information: * Permission to work on the computer without a current backup available * Release from liability if data is lost or corrupted * Description of the work to be performed | | 4.2.2 | | Identify the problem | |

| During the troubleshooting process, gather as much information from the customer as possible. The customer should provide you with the basic facts about the problem. Figure 1 lists some of the important information to gather from the customer.Conversation Etiquette
When you are talking to the customer, you should follow these guidelines: * Ask direct questions to gather information. * Do not use industry jargon when talking to customers. * Do not talk down to the customer. * Do not insult the customer. * Do not accuse the customer of causing the problem.By communicating effectively, you will be able to elicit the most relevant information about the problem from the customer.Open-Ended Questions
Open-ended questions are used to obtain general information. Open-ended questions allow customers to explain the details of the problem in their own words. Figure 2 shows some examples of open-ended questions.Closed-Ended Questions
Based on the information from the customer, you can proceed with closed-ended questions. Closed-ended questions generally require a "yes" or "no" answer. These questions are intended to get the most relevant information in the shortest time possible. Figure 3 shows some examples of closed-ended questions.Documenting Responses
Document the information obtained from the customer in the work order and in the repair journal. Write down anything that you think might be important for you or another technician. Often, the small details can lead to the solution of a difficult or complicated problem. It is now time to verify the customer's description of the problem by gathering data from the computer.Event Viewer
When system, user, or software errors occur on a computer, the Event Viewer is updated with information about the errors. The Event Viewer application shown in Figure 4 records the following information about the problem: * What problem occurred * Date and time of the problem * Severity of the problem * Source of the problem * Event ID number * Which user was logged in when the problem occurredAlthough the Event Viewer lists details about the error, you might need to further research the solution.Device Manager
The Device Manager shown in Figure 5 displays all of the devices that are configured on a computer. Any device that the operating system determines to be acting incorrectly is flagged with an error icon. This type of error has a yellow circle with an exclamation point (!). If a device is disabled, it is flagged with a red circle and an "X". A yellow question mark (?) indicates that the hardware is not functioning properly because the system does not know which driver to install for the hardware. Beep Codes
Each BIOS manufacturer has a unique beep sequence for hardware failures. When troubleshooting, power on the computer and listen. As the system proceeds through the POST, most computers emit one beep to indicate that the system is booting properly. If there is an error, you might hear multiple beeps. Document the beep code sequence, and research the code to determine the specific hardware failure.BIOS Information
If the computer boots and stops after the POST, investigate the BIOS settings to determine where to find the problem. A device might not be detected or configured properly. Refer to the motherboard manual to make sure that the BIOS settings are accurate.Diagnostic Tools
Conduct research to determine which software is available to help diagnose and solve problems. There are many programs available that can help you troubleshoot hardware. Often, manufacturers of system hardware provide diagnostic tools of their own. For instance, a hard drive manufacturer, might provide a tool that you can use to boot the computer and diagnose why the hard drive does not boot Windows. | | 4.2.3 | | Establish a theory of probable causes | |

| The second step in the troubleshooting process is to establish a theory of probable causes. First, create a list of the most common reasons why the error would occur. Even though the customer may think that there is a major problem, start with the obvious issues before moving to more complex diagnoses. List the easiest or most obvious causes at the top with the more complex causes at the bottom. You will test each of these causes in the next steps of the troubleshooting process | | 4.2.4 | | Determine an exact cause | |

| The next step in the troubleshooting process is to determine an exact cause. You determine an exact cause by testing your theories of probable causes one at a time, starting with the quickest and easiest. Figure 1 identifies some common quick tests. After identifying an exact cause of the problem, determine the steps to resolve the problem. As you become more experienced at troubleshooting computers, you will work through the steps in the process faster. For now, practice each step to better understand the troubleshooting process.If the exact cause of the problem has not been determined after you have tested all your theories, establish a new theory of probable causes and test it. If necessary, escalate the problem to a technician with more experience. Before you escalate, document each test that you try. Information about the tests is vital if the problem needs to be escalated to another technician, as shown in Figure 2. | | 4.2.5 | | Implement the solution | |

| After you have determined the exact cause of the problem, establish a plan of action to resolve the problem and implement the solution. Sometimes quick procedures can determine the exact cause of the problem or even correct the problem. If a quick procedure does correct the problem, you can go to step 5 to verify the solution and full system functionality. If a quick procedure does not correct the problem, you might need to research the problem further to establish the exact cause.Evaluate the problem and research possible solutions. Figure 1 lists possible research locations. Divide larger problems into smaller problems that can be analyzed and solved individually. Prioritize solutions starting with the easiest and fastest to implement. Create a list of possible solutions and implement them one at a time. If you implement a possible solution and it does not work, reverse the solution and try another. | | 4.2.6 | | Verify solution and full system functionality | |

| After the repairs to the computer have been completed, continue the troubleshooting process by verifying full system functionality and implementing any preventive measures if needed. Verifying full system functionality confirms that you have solved the original problem and ensures that you have not created another problem while repairing the computer. Whenever possible, have the customer verify the solution and system functionality. | | 4.2.7 | | Document findings | |

| After the repairs to the computer have been completed, finish the troubleshooting process by closing with the customer. Communicate the problem and the solution to the customer verbally and in all documentation. Figure 1 shows the steps to be taken when you have finished a repair and are closing with the customer.Verify the solution with the customer. If the customer is available, demonstrate how the solution has corrected the computer problem. Have the customer test the solution and try to reproduce the problem. When the customer can verify that the problem has been resolved, you can complete the documentation for the repair in the work order and in your journal. The documentation should include the following information: * Description of the problem * Steps to resolve the problem * Components used in the repair | | 4.3 | | Summary | |

| This chapter discussed the concepts of preventive maintenance and the troubleshooting process. * Regular preventive maintenance reduces hardware and software problems. * Before beginning any repair, back up the data on a computer. * The troubleshooting process is a guideline to help you solve computer problems in an efficient manner. * Document everything that you try, even if it fails. The documentation that you create will become a useful resource for you and other technicians. | |