Appendix A -- Questions and Answers | Microsoft Corporation

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Chapter 1

Give several examples of early electronic computers.

Among the early electronic computers were the Atanasoff-Berry Computer (ABC), ENIAC (Electronic Numerical Integrator and Computer), and Colossus.

What are the three roles that today's computer service professional needs to assume?

Today's computer professional needs to be a technician, a scholar, and a diplomat.

Chapter 2

What is the definition of a bus in a computer?

A computer bus is a group of electrical conductors (usually wires) running parallel to each other. These conductors can be copper traces on a circuit board or wires in a cable. Usually, they are found in multiples of eight (8, 16, 32, 64, and so on).

What is the purpose of the computer bus?

The purpose of the computer bus is to provide a common path to transmit information, in the form of code, to all parts of the computer.

Define the term "digital."

Digital, as it is used in this book, refers to the binary digits 0 (off) and 1 (on).

Describe the difference between serial and parallel communication.

Serial communication sends each piece of information one bit at a time on one wire, and parallel communication sends as many bits of information at a time as there are parallel wires.

What is binary code language?

Binary code language is computer language. The language is called binary because it is based on two states or numbers (0 and 1) represented by a switch condition being set either on or off.

How does ASCII use binary code to represent numbers or characters?

Computers use the binary system for communication, based on eight bits (or one byte) of information being transmitted at one time. To support this, a standard code called ASCII (American Standard Code for Information Interchange) was developed as the basis for computer communication. Basic ASCII consisted of 128 binary codes that represented the English alphabet, punctuation, and certain control characters.

Define a bit.

A bit is the smallest unit of information that is recognized by a microcomputer. It is similar to a light bulb in that it can exist only in two states—it is either on or it is off.

Define a byte.

A byte is a group of eight bits. To represent one character of information requires one byte.

Which decimal number does the following binary number represent: 00001001?

This binary number represents the number 9.

What do 1s and 0s represent in computer operation?

1s and 0s represent voltage to a computer: the absence of voltage represents a 0 bit, and the presence of voltage represents a 1 bit.

Computer buses are usually found in multiples of _______ wires or traces.

Computer buses are usually found in multiples of 8 wires or traces.

Chapter 3

What are the three stages of computing?

The three stages of computing are input, processing, and output.

What is the purpose of the central processing unit (CPU)?

The central processing unit (CPU) is the heart and brain of the computer. This one component or "chip" does all the number crunching and data management.

Describe two devices that process information inside a computer.

The CPU and the chip set process information inside a computer.

What is a chip set?

A chip set is a group of computer chips or ICs (integrated circuits) that, when working in harmony, manage and control the computer system.

Give three examples of input devices.

The mouse, keyboard, microphone, and scanner are examples of input devices.

What type of device is a scanner?

A scanner is an input device.

Give three examples of output devices.

The printer, monitor, and speakers are examples of output devices.

What is I/O?

Many devices can handle both input and output functions. These devices are called I/O devices.

Give four examples of I/O devices.

The floppy disk drive, hard disk drive, modem, and network interface card are examples of I/O devices.

Chapter 4

What is the language of the computer?

Binary code is the language of the computer.

What is an external data bus?

The external data bus is the primary bus for handling the flow of data. All devices that process data are connected to the external data bus.

Describe an integrated circuit (IC).

An integrated circuit is an electronic device consisting of many miniature transistors and other circuit elements (resistors and capacitors, for instance).

Define a clock cycle.

The timing for all activities within a computer is set by the computer's clock (but not the one that keeps time). Each pulse of voltage produced by the clock is called a "clock cycle."

What are the advantages of a Pentium processor over a 486?

Many improvements were made to the Pentium chip that made it superior to the 486, including:

Faster speeds.

A 32-bit address bus and 32-bit registers.

A 64-bit data path to improve the speed of data transfers.

A dual pipeline, 32-bit data bus that allows the chip to process two separate lines of code simultaneously.

A write-back cache of at least 8-KB for data and an 8-B write-through cache.

Branch prediction—the program cache attempts to anticipate branching within the code.

What is the difference between "SX" and "DX" in a 386 chip?

The 80386DX was a true 32-bit processor with a 32-bit external data bus, 32-bit registers, and a 32-bit address bus (enabling 4 GB of memory to be accessed). The 80386SX was similar to the DX except that it had a 16-bit external data bus and a 24-bit address bus (it could address only 16 MB of memory).

Which computers use the Motorola 68040 chip?

Some Apple Macintoshes use the Motorola 68040 chip.

Define microprocessor.

A microprocessor is an integrated circuit that contains a complete CPU on a single chip.

In computer code language _________ means on and _________ means off.

In computer code language the number 1 means on and the number 0 means off.

Define clock speed.

Clock speed, a main selling point for today's PC computer, is the system clock rate, measured in megahertz (MHz). One MHz equals one million cycles per second. Clock speed is the number of times per second that a computer can process an instruction.

What is the function of the address bus?

The CPU accesses memory through an additional bus called the address bus. The number of conductors in the address bus determines the maximum amount of memory that can be used by the CPU.

Microprocessor chips (CPUs) are manufactured in a variety of sizes and shapes. Name as many different kinds as possible.

Examples of chip packages are DIPP, PGA, PLCC, and PQFP.

Name the basic types of CPU sockets.

The LIF (low-insertion-force) and ZIF (zero-insertion-force) sockets are the two basic CPU sockets. The Pentium II and later Intel processors use Slot 1 sockets.

If a customer brought you an old Pentium 60-based computer and asked you to install a new processor, what would your advice be?

Consider upgrading the CPU and motherboard to a newer CPU and matching motherboard.

Chapter 5

Explain the difference between spikes, surges, and sags.

Spikes and surges are brief, but often catastrophic, increases in the voltage source (very high voltage for a very short time). These can be caused by the power source (the local power company), but most often are caused by lightning strikes. A spike (or transient) is a very short over-voltage condition measured in nanoseconds, while a surge is measured in milliseconds. A sag is a brief decrease of voltage at the source.

What are the two types of power-supply connectors to the motherboard?

AT style with two plugs—P8 and P9, and the ATX style with a single connector.

What are the two types of power-supply connectors to devices such as drives?

The Molex, a 5-volt connector, is used for hard disk drives, and the mini 3.3-volt is used for floppy disk drives and similar devices.

Name two benefits to having a UPS on a system.

The UPS (uninterruptible power supply) buys the user some time in which to save data and properly shut down a system, in the event that a power outage has occurred. And the UPS conditions the line in the event of a spike or surge.

Describe the difference between a brownout and a blackout.

A brownout is a decrease in the voltage in the power supply. A blackout is a total power failure.

When you purchase a UPS, what is the most important thing to consider?

That the UPS offers enough time to power the computer until all data can be saved and the computer can be properly shut down.

Will all surge suppressors provide protection against lightning strikes?

No, surge suppressors offer limited protection, and it decreases with age. Also, nothing can totally protect against a nearby full-force lightning strike.

What is the best defense against spikes caused by lightning?

To protect against spikes from lightning, unplug your computer from the wall outlet.

What is the most important thing to remember when connecting a P8 and P9 connector to a motherboard?

The black (ground) wires must be installed next to each other.

Explain the difference between the mini connector and the Molex connector.

The Molex connector is the most common connector, and is used primarily for devices that need both 12-volt and 5-volt power, such as older floppy disk drives, hard disk drives, and CD-ROM drives.

The mini connector is used primarily on 3.5-inch floppy drives. Most systems provide a mini connector.

Describe the best way to make sure a new power supply matches the one you are replacing.

Take the old one with you and match its physical size, as well as the power ratings and number of connectors, to the new one.

What is the primary use of mini connectors?

Mini connectors are primarily used for 3.5-inch floppy disk drives.

A computer power supply has both 5-volt and 12-volt outputs. The 5-volt output is used to power ________________________________, and the 12-volt output is used to power ____________________________________.

The 5-volt output is used to power devices that manage data only, and the 12-volt output is used to power devices that have moving parts, such as drives and fans.

Chapter 6

What is the main function of the motherboard?

The motherboard is the primary card in the computer. It defines the limits for CPU type, speed, memory, and expandability.

Name the typical chips found in a chip set.

A motherboard comes with several chips soldered in place. They constitute the chip set and are designed to work with the CPU. These chips are highly complex and coordinated ICs that help the CPU manage and control the computer's system. Included in the chip set are the clock generator, bus controller, system timer, interrupt controller, DMA controller, CMOS, and keyboard controller.

What is EMI?

EMI stands for electromagnetic interference. EMI is the same thing as radio frequency interference (RFI), but EMI is a newer term. EMI is considered to be any radio frequency that is emitted from an electrical or electronic device that is harmful to the surrounding equipment or that interferes with the operation of another electrical or electronic device.

What are ROM chips used for?

ROM chips are used extensively to program the operation of computers, but ROM plays a limited role in the PC; it holds the BIOS information used to describe the system configuration and the instructions for performing the POST routine.

Name the three types of ROM chip.

The first type of ROM chip is called the core chip and includes hardware that is common, necessary, and unchanging. The second type of ROM chip is hardware that is common, necessary, and changeable; these chips are called updatable chips. The third type of chip includes any chip other than the first two types of chips.

Describe what makes the CMOS special.

The CMOS chips are updatable, and that makes them special. They do not store programs like other ROM chips do; they store only data that is used by BIOS for the programs needed to communicate with changeable hardware. The CMOS chip also maintains date-and-time information when the computer is powered off.

How can a technician use the POST beep codes?

The purpose of the first POST (power-on self test) is to check the most basic components. Because the video integrity has not been confirmed, any errors that occur in this phase are indicated by a series of beeps. A technician can use the beep codes to interpret any problems that occur before the video is confirmed.

What is a device driver?

A device driver is a program that acts as an interface between the operating system and the control circuits that operate the device.

What information is contained in the CMOS?

Typically, the CMOS contains at least the following information: floppy and hard disk drive types, CPU and memory size, date and time, and serial- and parallel-port information.

Define the POST and describe its function.

Every time a computer is turned on or reset, the entire system is reset. From this on or reset state, it begins to carry out software instructions from its BIOS program. The first set of instructions it initiates is a special program (stored on a ROM chip) called the power-on self test (POST). The POST sends out standardized commands that check every device (in more technical terms, it runs an internal self-diagnostic routine).

Chapter 7

What is hexadecimal shorthand used for?

Hexadecimal shorthand (hex, for short) is a numbering system used by designers and programmers to simplify the representation of numbers and notations. Known as "base-16 mathematics," it is a complete numbering system based on 16 instead of 10. Just as in the base-10 system, you can add, subtract, or do trigonometry with hex.

Define the following terms: conventional memory, expanded memory, extended memory, HMA, shadow RAM.

Conventional memory is the first 640 KB of memory in a computer. The first 1 MB of memory was divided into two sections: 384 KB of RAM (designated upper memory) for running the computer (BIOS, video RAM, and ROM), and 640 KB for applications (designated).

Expanded memory is memory that conforms to the EMS specification, developed by Lotus, Intel, and Microsoft. It requires a special device driver. EMS is accessed through 64-KB blocks of the upper memory.

Extended memory is any memory beyond the first 1 MB.

HMA is the first 64 KB of extended memory on machines with 80286 or higher processors.

Shadow RAM rewrites (or shadows) the contents of the ROM BIOS and/or video BIOS into extended RAM memory (between the 640-KB boundary and 1 MB). This allows systems to operate faster when application software calls for any BIOS routines.

Describe the difference between ROM and RAM.

ROM is read-only memory and cannot be changed. It is usually used for BIOS or other data that cannot be lost if the power is off.

RAM is random access memory and is constantly changing. It is used as the main working memory for a computer. RAM memory is lost if the power is turned off.

How many 30-pin SIMM boards are required for one bank of memory on a computer with a 486 processor?

Because a 486 computer has a 32-bit external data bus, it requires four 30-pin SIMMs per bank. Remember, a 30-pin SIMM is only one byte (8-bits) wide; therefore, you need to divide the width of the bus by the width of the SIMM—that is, 32 (the width of data bus) divided by 8 (the number of bits per SIMM module).

What is the difference between "write-through" and "write-back" cache?

Some caches immediately send all data directly to RAM, even if it means hitting a wait state. This is called write-through cache. Some caches store the data for a time and send it to RAM later. This is called a write-back cache.

What is DRAM?

DRAM (dynamic random access memory) is volatile memory that works only when the computer has power. This is the "scratch pad" that the CPU uses to manipulate data.

Define access speed.

The time required to complete a memory read or to write actions is known as the access speed of the memory chip. This time is usually very small and is measured in nanoseconds (one-billionth of a second—abbreviated as ns). The faster the chip, the smaller the access-speed number.

Describe the major difference between SIPPs and SIMMs.

A SIPP (single inline pin package) is a printed circuit board with individual DRAM chips mounted on it. SIMMs (single inline memory modules) are the new generation of memory chips. They are similar to SIPPs, with one exception—SIMMs have no pins, as such. 30-pin SIMMs have 30 contacts along the edge.

Define cache memory.

To cache means to set something aside, or to store nearby, for anticipated use. Mass storage (disk drives) is much slower than RAM, and RAM is much slower than the CPU. Caching increases the speed of the system by creating special storage areas in high-speed memory.

One of the differences between DRAM and SRAM is that SRAM does not have to be refreshed. What does this mean, and how does it affect the cost of each type of chip?

Refreshing means that the information must be updated constantly or it will be lost. SRAM does not require that extra step that can slow things down (nothing can access the memory during a refresh). Because SRAM is faster, the circuitry required is more expensive.

Chapter 8

What is the purpose of an IDE drive?

The IDE (Integrated Drive Electronics) drive was introduced in the early 1990s. The IDE quickly became the standard for general-purpose computers. The purpose of the IDE specification was to increase data throughput, support non-hard disk drive storage devices, increase the capacity of hard drives beyond the 528-MB barrier, and to allow connection of up to four devices instead of only two.

How many drives can be connected to a single IDE connector?

Two drives can be connected to one IDE connector.

What is the best method of determining the number of drives available on a computer?

The best method of determining the number of drives available on a computer is to run the CMOS setup program. Originally, the CMOS would only allow for two drives. Later versions allow up to four drives.

What three things should be checked when a floppy disk drive fails?

Three things to check when a floppy disk drive fails are the floppy disk itself (not the drive), the CMOS setup, and the drive controller/power supply cables.

What is the best way to ensure long life from a floppy disk drive?

To ensure long life from a floppy disk drive, keep it clean.

When you purchase a new floppy disk drive controller, what can you expect to receive with it?

Floppy disk drive controller cards also include some or all of the following: hard disk drive controllers, serial ports, parallel ports, and game ports. If the new card contains any ports that duplicate ports already present elsewhere on the computer (on the motherboard, for instance), a potential conflict exists.

Other than physical size, what are the only differences between a 5.25-inch floppy disk drive and a 3.5-inch floppy disk drive?

The only difference between a 5.25-inch and a 3.5-inch drive (other than physical size) is that a 5.25-inch drive has a slot connector and a 3.5-inch drive has a pin connector for engaging and spinning the disk.

What type of cable is used to connect a floppy disk drive to the external data bus?

All floppy disk drives are connected to the motherboard (external data bus) by a 34-conductor ribbon cable. This cable has a seven-wire twist in lines 10 through 16. This ensures that when two floppy disk drives are attached, the drive-select and motor-enable signals on those wires can be inverted to "select" which drive becomes the active target. The other wires carry data and ground signals.

What is the proper way to install a floppy disk drive cable?

The connector end of the cable, with the twist, always goes toward the drives.

To which pin must the Number 1 wire of the floppy disk drive control cable be connected?

This red (or sometimes blue) wire is connected to the number 1 pin on the drive's controller connector. (The number 1 pin is usually located next to the power connection.)

You've received the following error message: "General failure reading Drive A:". What is the most likely problem?

The CMOS settings for the A drive are the most likely cause. Always double-check the CMOS if you are experiencing a recurrent drive failure. Checking is quick, easy, and can save you time.

Are floppy disk controllers sensitive to ESD?

Yes, floppy disk controllers are sensitive to ESD (electrostatic discharge).

You receive an error message that ends with "Abort, Retry, Fail?" What is the most likely cause of the error?

This error message indicates a failure to read the drive. These errors are the easiest to fix and can usually be attributed to a bad sector on the drive.

Why is a voice coil actuator arm better than a stepper motor actuator arm?

A voice coil actuator arm has several advantages over the stepper motor actuator arm. The lack of mechanical interface between the actuator arm and the motor provides consistent positioning accuracy. When the drive is shut down (the power is removed from the coil), the actuator arm (which is spring-loaded) moves back to its initial position, thus eliminating the need to park the head. In a sense, these drives are self-parking.

Define hard disk drive geometry.

Hard disk drives are composed of one or more disks, or platters, on which data is stored. The geometry of a hard drive is the organization of data on these platters. Geometry determines the maximum storage capacity of the drive.

What is the best way to determine the geometry of an unknown drive?

The geometry or type of many hard disk drives is labeled directly on the hard drive itself.

Describe HDI.

Head to Disk Interference (HDI) is another term for head crash.

The BIOS limits the number of heads to a maximum of __________.

The maximum number of heads is 16.

The BIOS limits the number of cylinders to a maximum of __________.

The maximum number of cylinders is 1024.

How many bytes of data does a sector hold?

One sector holds 512 bytes of data.

What is the maximum number of sectors per track?

The maximum number of sectors per track is 63.

What does CHS stand for?

CHS stands for cylinders, heads and tracks per sector.

What type of drive is standard on today's personal computer?

The IDE is the standard drive on today's personal computers.

Describe the characteristics of the different hard disk drive types.

The first hard disk drives for personal computers used the ST-506/412 interface. The ST-506/412 was the only hard drive available for the IBM computer and the first to be supported by the ROM BIOS chip on the motherboard.

The Enhanced Small Device Interface (ESDI) was introduced in 1983 by the Maxtor Corporation. Beginning with this drive, most controller functions were incorporated directly onto the hard disk drive itself.

The Small Computer System Interface (SCSI) has been around since the mid 1970s in one or another form. Apple adopted the SCSI as its expansion bus standard. The SCSI bus functions as a communications pathway between the computer system bus and the SCSI device controller.

What is a partition? What are the two types of partition?

Partitions are logical divisions of a hard disk drive. A computer might have only one physical hard drive (called hard drive 0), but it can have anywhere from one to 24 logical drives, called C to Z.

There are two types of partitions: primary and extended.

Define a cluster.

A cluster is a combined set of contiguous sectors which the FAT treats as a single unit. The number of sectors in each cluster is determined by the size of the partition. There can never be more than 64,000 clusters.

What is the FAT and how does it work?

The FAT (file allocation table) is simply an index that keeps track of which part of the file is stored in which sector. Each partition (or floppy disk) has two FATs stored near the beginning of the partition. These FATs are called FAT 1 and FAT 2. They are identical. Each FAT can be looked at as a two-column spreadsheet.

What is fragmentation?

Fragmentation is the scattering of parts of the same disk file over different areas of the disk. When files are scattered all over a drive in noncontiguous clusters they are said to be fragmented.

How can you minimize the impact of a hard disk drive failure?

To minimize the impact of a hard disk drive failure, perform comprehensive, frequent backups, and save a copy of the boot sector and partition table.

What is the function of ScanDisk?

ScanDisk performs a battery of tests on a hard disk. These include looking for invalid filenames, invalid file dates and times, bad sectors, and invalid compression structures. In the file system, ScanDisk looks for lost clusters, invalid clusters, and cross-linked clusters.

Chapter 9

Name four methods of overcoming the 528-MB hard disk limitation.

The first method utilizes Logical Block Addressing (LBA mode)—a means of addressing the physical sectors on a hard disk drive in a linear fashion.

The second method utilizes Enhanced CHS—a standard that competes with LBA. This standard allows drives to be manufactured a little faster and more easily than LBA.

The third method utilizes Fast ATA, which uses PIO mode 3, and Fast ATA-2, which uses PIO mode 4.

The fourth method utilizes logical cylinders, heads, and sectors (L-CHS)—a value used by the operating system (for instance, MS-DOS, Windows 95 and Windows 98, OS/2) to determine the size of the hard drive.

How do multiple block reads speed up a computer?

The ATA standard requires each drive to activate its IRQ every time it sends one sector of data. This process helps to verify good data transmission, but it slows down the computer. Multiple block reads speed up the process by reading several sectors of data at a time.

How many devices can be installed on a SCSI chain?

Eight devices can be installed on a single SCSI-1 chain. However, one of those devices must be reserved for the SCSI controller. SCSI-2 and later host adapters allow up to 16, with one reserved for the host adapter. Some SCSI cards offer multichannel support and can handle even more.

What is the effect of improper termination on a SCSI chain or device?

Improper termination can cause a failure to boot, the "disappearance" of a device from the SCSI chain, erratic behavior, and—in extreme cases—can even destroy a SCSI device.

What is the BIOS protocol for SCSI devices?

The BIOS protocol for SCSI devices is the Advanced SCSI Programmers Interface (ASPI).

Sometimes the SCSI device driver conflicts with other drivers. What steps need to be taken to resolve the problem?

Often, the only way to tell if there will be a conflict is to try the driver and see what happens. Remember to document every step you take so that you can undo any changes. Load only the device drivers for the SCSI devices.

If the problem occurs, use the F8 key to determine which driver conflicts. (Press F8 when starting MS-DOS or Windows 95 or Windows 98—this will allow step-by-step confirmation of the startup process.)

If the device driver is an executable file, try running it with the "/?" option. This will usually show a variety of command-line switches for the device driver (for example, "mouse.exe /?").

Describe at least three advantages of using a CD-ROM drive.

Advantages of using CD-ROM drives include: large storage capacity, sturdiness, portability, and the fact that data on the disk cannot be changed.

What are the four steps required to install a CD-ROM drive?

Install the drive controller card, if needed.

Install the CD-ROM drive in the computer case.

Attach the data and power cables.

Install the necessary drivers and set up the CD-ROM drive.

Is a 16X CD-ROM drive 16 times faster than a 1X?

No, it is not. The 16X CD-ROM data transfer rate will be 16 times faster, but the mean access time is not 16 times faster.

How would you determine which type of CD-ROM drive to install in a computer?

You first have to determine whether or not there is room inside the case and if there are any available IDE controller connections. If not, then consider an external drive. If you want a SCSI controller, you will have to make sure there is an available slot in the expansion bus.

Why would you use the MSCDEX.EXE real-mode driver with Windows 95?

Windows 95 and Windows 98 use virtual drivers and do not need the MSCDEX.EXE real-mode driver. However, if you intend to use a CD-ROM drive in the MS-DOS mode (from a bootable disk), the real-mode drivers will have to be installed and added to the CONFIG.SYS and AUTOEXEC.BAT files of the boot disk.

Instead of using magnetic energy for storing data, a CD-ROM uses _______ technology.

A CD-ROM uses laser technology.

Name some possible controller card combinations.

There are several ways to combine controller cards: use the secondary IDE controller on the motherboard; use a new controller card (supplied with the CD-ROM); use an existing SCSI chain; use a SCSI host adapter, create a new SCSI chain; or use an existing sound card with a CD connection.

What software is required for a CD-ROM drive installation?

The driver that came with the CD-ROM and the Microsoft MSCDEX.EXE program, are required for a CD-ROM drive installation.

Chapter 10

Why does a computer need an expansion bus?

Expansion slots on the motherboard are standardized connections that allow the installation of any device not soldered to the motherboard. By providing this connection to the expansion bus, computers can be customized to meet the requirements of the user.

Name the available expansion buses.

The available expansion buses are: ISA, MCA, EISA, VESA, AGP, and PCI.

What happens if two non-PCI devices use the same I/O address?

The computer will lock up.

How many IRQs are available on most PCs?

There are 15 IRQs available, although some of them are permanently assigned.

Under what conditions would a second modem—installed and assigned to COM3—not work?

If the first modem had been using COM1, the failure would be the result of an IRQ conflict. Devices assigned to COM1 and COM3 both make use of IRQ4. If the first modem has already been assigned to COM1, a conflict will occur when both modems make use of IRQ4.

One solution is to assign COM3 an available interrupt such as IRQ10.

Identify the two divisions of the external data bus and describe the purpose of each.

The two divisions of the external data bus are the system bus and the expansion bus. The system bus supports the CPU, RAM, and other motherboard components. The system bus runs at speeds that support the CPU.

The expansion bus supports any add-on devices via the expansion slots and runs at a steady 7.16 MHz.

What is the standard that governs computer buses?

IBM established the ISA industry standard, thus generating the market for clones. The term ISA (Industry Standard Architecture) did not become official until 1990.

What is the difference between ISA and EISA cards?

EISA uses a double slot connector that is compatible with ISA devices. Physically, the EISA bus is the same size and looks similar to the ISA. However, they differ in the number of contacts and the depth of the slot. On close inspection, you can see a double set of contacts (one above the other).

Why was VESA created?

The Video Electronics Standards Association (VESA) is a trade association of display-adapter vendors. It was created to address the need for faster video to support the increased demands of new graphical operating systems like Windows and OS/2. These environments called for far better graphics and color management than the older character-based operating systems like CP/M.

What is bus mastering?

Bus mastering allows a device to gain control of the bus to perform special tasks without processor intervention.

Describe ways in which the PCI bus is better than previous technologies.

The PCI (Peripheral Component Interconnect) bus was designed by Intel to be a stronger, more flexible alternative to the current expansion buses while maintaining backward compatibility. It is independent of the CPU, so it is better than the VL bus and is not limited to use in 486-based computers.

How does the CPU use I/O addresses?

The CPU uses the unique address (actually a block of addresses) to communicate with a device in the system using the bus.

What is the I/O port address of COM2?

The I/O port address of COM2 is 2F8.

What are the functions of IRQs?

An IRQ is used by a device to send a request to the CPU for permission to transmit data so that all devices do not attempt to communicate at the same time.

List as many of the standard IRQ assignments as you can.

Here is a list of IRQ assignments. How many did you get?

IRQ	Function
IRQ 0	System timer
IRQ 1	Keyboard controller
IRQ 2/9	Available
IRQ 3	COM2, COM4
IRQ 4	COM1, COM3
IRQ 5	LPT2
IRQ 6	Floppy disk controller
IRQ 7	LPT1
IRQ 8	Real-time clock
IRQ 10	Available
IRQ 11	SCSI/available
IRQ 12	Available
IRQ 13	Math coprocessor
IRQ 14	Primary IDE controller
IRQ 15	Secondary IDE controller

What is the function of the DMA chip?

The only function of the DMA chip (8237) is to move data. It handles all data passing from peripherals to RAM and vice versa.

Why is it important not to assign an IRQ to more than one device?

If two devices have the same IRQ and try to communicate with the CPU at the same time, the resulting conflict will lock up the computer.

What is the difference between COM ports and LPT ports?

COM ports are for serial communications, and LPT ports are parallel ports normally used with printers.

Why is it important to document IRQs, DMAs, and I/O addresses?

Because these three things cause more conflicts than perhaps anything else in a computer, you will be able to reduce installation times and correct conflicts.

Chapter 11

Describe the three elements that make up one dot of color.

One dot of color is made up of three smaller dots: one red, one green, and one blue.

What is the advantage of interlacing? Is it worth doing?

Interlacing is a way of arranging a video display so that the CRT sweeps all the odd-numbered rows and then all the even-numbered rows (or vice versa). The intention of interlacing is to reduce the flicker on the screen by increasing the refresh rate (in other words, scanning the screen twice as often). An interlaced monitor can be well-suited for stand-alone servers or computers that run for long hours unattended. It might be a good choice when there will be little interaction by an operator or when cost is a primary factor. Interlacing should be avoided for normal use, because it can lead to eyestrain and headaches.

Should a monitor be turned on and off, or left on all day?

The most basic form of power management is to turn off the monitor, using the power switch. At the same time, the CRT is the most expensive component of a monitor and can be damaged when it is turned on and off too frequently. Because these two concepts contradict each other, there is no single correct answer. You will have to make a decision based on the customer's individual circumstances.

What is the "standard" type of video card used with today's computers?

Some variation of the SVGA video card is used on most computers sold today.

What is the formula for calculating the required memory for a monitor/video card combination?

The formula is: video memory requirement = horizontal pixels x vertical pixels x color depth.

What does CRT stand for?

It stands for cathode-ray tube.

What are HRR and VRR?

The number of times per second an electron beam sweeps is called the refresh rate. The speed at which the electron beam completes one horizontal trace is known as the horizontal refresh rate (HRR). The time taken by the monitor to complete all horizontal traces and return to the top of the screen is the vertical refresh rate (VRR).

Define resolution.

Resolution is the measurement of image detail produced by a monitor or printer. Monitor resolution is expressed as the number of horizontal pixels by the number of vertical pixels.

What is bandwidth?

With computer monitors, bandwidth is the maximum number of times per second an electron gun can be turned on and off. Bandwidth is measured in megahertz (MHz—millions of cycles per second). A typical value for a high-resolution, 17-inch color monitor would be around 100 MHz.

Why is it dangerous to open the monitor's cover?

The CRT part of a monitor acts like a large capacitor and is capable of holding a very large charge (30,000 volts).

Name four common sources of video problems.

The video-signal cable, video controller card, video-driver software, and the monitor are the four primary sources of video problems.

Explain one similarity and one difference between VRAM and WRAM.

Both offer dual port reads and writes, but WRAM is faster and less expensive.

What is a raster?

Video data is displayed on the monitor by sweeping the electron gun(s) in a series of horizontal lines or traces across the display. The line created by each sweep is called a raster. The number of rasters is used to describe the vertical resolution of a monitor.

What type of connector is used for an SVGA monitor?

The PGA, VGA, and SVGA monitor each use a 15-pin, three-row, female DB connector.

Chapter 12

Name three types of printers and describe their advantages and disadvantages.

Impact printers produce an image on paper by physically striking an inked ribbon against the surface of the paper. The advantages of impact printers are that they tend to be inexpensive and print at a relatively high speed. Impact printers were very popular in the late 1980s. Some disadvantages of impact printers are lower print quality and noise.

Ink-jet printers have replaced dot-matrix printers at the low end of the market. Many computer manufacturers and large computer stores offer ink-jet printers along with computers as part of package deals. They produce good-quality printing and are relatively fast, while requiring little maintenance beyond replacing the cartridge. What makes them attractive is their ability to easily produce color, as well as standard black-and-white images. High-quality color ink-jet printers are available; however, high-quality color printing comes at a cost. It requires a good printer and special paper that will prevent "wicking" of the ink, which causes a fuzzy appearance.

Laser printers have become one of the most popular types of printer for home use and are a must for most office environments. They produce high-quality, high-speed printing. Early laser printers were notorious for generating lots of heat and consuming lots of power.

The dot-matrix printer is an ____________ printer. Name at least one advantage of this type of printer. Name at least one disadvantage.

A dot-matrix printer is an impact printer. Its main advantages are its ability to print forms (multiple pages) and its high reliability and low operating cost. Its disadvantages are its noise, slow speed, and generally low-quality (by today's standards) images.

What are the six steps of laser printing?

Clean the drum.

Charge the drum.

Write the image.

Transfer the toner.

Transfer the image.

Fuse the image.

Which components are usually included in a laser printer's replaceable toner cartridge? Why?

Many of a laser printer's critical components, including those that experience the most wear and tear, are incorporated into the toner cartridge. The most important is the photosensitive drum. By incorporating these components into the toner cartridge, chances of failure are reduced because the primary-wear components are constantly replaced.

What causes black spots to appear on a document that has been printed on a laser printer? How can this problem be resolved?

If residual particles remain on the drum, they will appear as random black spots and streaks on the next printed page. The drum will need to be cleaned to clear this problem.

What is the IEEE 1284 standard?

There is a vast array of printers available and in order to ensure that you are obtaining optimum performance, the printer, the printer driver, and the software using the printer must be configured for the same mode. The IEEE 1284 standard establishes the standards to ensure printer compatibility.

What kinds of signals do telephones use? What kinds of signals do computers use?

Computers transfer data by means of parallel wires or buses. Computer modems use serial communication. Telephone systems use only two wires.

What is the purpose of a modem?

A modem is a peripheral device that enables computers to communicate with each other over conventional telephone lines and through wireless communication.

Which AT command is used to take the phone off the hook?

The ATH command takes the phone off the hook.

What is the difference between baud and bps?

Baud is limited to 2400 cycles per second. Baud rate is limited by the capability of copper wires to transmit signals. Bps represents the actual number of data bits that can be transmitted per second.

What is the name of the chip that converts data from parallel to serial?

This chip is called a UART (universal asynchronous receiver-transmitter).

Name three transfer protocols.

Three protocols for synchronous communication are Xmodem, Ymodem, and Zmodem.

What is Zmodem? What are its advantages over other protocols?

Zmodem shares all the features found in Xmodem and Ymodem protocols. It also adds a few new features, including crash recovery, automatic downloading, and a streaming file-transfer method. It is the protocol of choice for most telecommunication operations.

Define handshaking.

Handshaking is the negotiation of the rules (protocols) of communication between two modems.

What are AT commands and how can a computer technician use them?

AT commands are text commands that can be used to provide instructions to a modem. They are all preceded by the letters "AT." These commands are very useful as diagnostic tools for today's computer professional. To use these commands, make sure the communication software is loaded and the computer is in terminal mode. Unless the modem is set up to autoconnect (online mode), it will be in command mode and ready to accept AT commands.

Explain the difference between half-duplex and full-duplex. What makes them different? Where or when is each used?

In half-duplex, the RJ-11 plug has only two wires; therefore, only one signal can be sent or received at a time. Half-duplex is used to send messages in only one direction, like a fire alarm signal.

In full-duplex, the RJ-12 plug uses four wires (for two phones). It is the same size as the RJ-11 but with two additional wires. This enables users to send and receive data simultaneously.

What is the difference between synchronous and asynchronous communication?

Asynchronous communication is data transmission in which the length of time between characters may vary. Timing is dependent on the actual time it takes for the transfer to occur. This differs from synchronous communication, which is timed rigidly by an external clock.

Synchronous communication is a form of communication in which blocks of data are sent at strictly timed intervals. Because of this timing, no start or stop bits are required. Synchronous communication is more reliable than asynchronous and, therefore, more widely used.

Why are fax standards different from modem standards?

Faxes involve a different technology from that used by modems and are developed by different standards committees and operate on technology defined in a different standard than modems. A fax can be a stand-alone machine or incorporated into a computer. Computer faxes allow you to use the same format as picture reproduction (they paint a page of black-and-white pixels).

Describe a null-modem cable.

Null-modem cables are used to directly connect two computers together without the need for a modem. The transmit and receive wires in the cable (wires 2 and 3) are switched to make the computers "think" they are using modems.

In addition to the cost of the printer, what other costs should be considered when purchasing a printer?

You should always consider the total operating cost, including the cost of paper and ink or toner.

What does bps stand for?

Bps stands for bits per second.

Identify as many cables and connectors as you can.

Here is a table of connectors. How many did you get right?

Name	Uses
DB-9	Serial ports—external modem, mouse, printer.
DB-25	Parallel Port—printer, scanner, removable drive.
RJ-11	Standard telephone connector—2 wires.
RJ-12	Standard telephone connector—4 wires—used with dual phone connections.
RJ-45	Network connector.
PS/2 (mini-DIN)	Mouse, scanners.
Centronics	Printers.
USB	Universal serial bus—Technology that allows multiple peripherals to be attached to one cable.

What type of connector is used for a parallel port on the computer?

A 25-pin female connector is used for a parallel port on the computer.

What type of connector is used for a parallel port on the printer?

The most common parallel connector on the printer is the Centronics connector.

Chapter 13

What is Ohm's Law?

Ohm's Law states that the current (electrons) flowing through a conductor, or resistance, is in linear proportion to the applied potential difference (volts).

What is the formula for Ohm's Law?

The formula for Ohm's Law is voltage is equal to the current multiplied by the resistance (V = I R).

What is the difference between AC and DC?

AC is alternating current in which the voltage varies from positive to negative. DC is direct current in which the voltage stays the same all the time.

What instrument is used to measure the various components of electricity?

The instrument used to measure the various components of electricity is VOM—Volt-Ohm Meter (sometimes referred to as DVOM or Digital Volt-Ohm Meter).

How do you test for continuity?

Continuity is a term used to indicate whether or not there is a connection from one point to another. It is used to determine the presence of breaks in wires and electrical circuits. If no continuity setting is available, use the resistance setting. If the multimeter measures infinite resistance, then there is no continuity, indicating a break in the circuit. If the multimeter shows little or no resistance, then there is continuity and the circuit is complete.

What is "AC Ripple?" How do you test for it?

A power supply converts AC to DC voltage. When working properly, a pure DC signal will be produced. Sometimes, however, as the power supply ages, its ability to produce pure DC falters. A power supply uses capacitors to filter or smooth the voltage after being converted from AC to DC. These capacitors are second only to fuses as the part of a power supply most likely to fail. When a capacitor begins to fail, it allows more and more AC voltage to pass through. This AC voltage is superimposed on top of the DC voltage and is called noise or ripple.

To test for ripple, set a meter to read AC. Then connect a .1mfd capacitor to the red lead. With the power turned on, measure the DC voltage to ground. Any ripple present will be displayed as an AC voltage.

Describe ESD and how to prevent it.

Just as high voltages generated by electrical and electronic equipment can do severe damage to humans, high voltages generated by humans can do damage to computers. We have all seen what a short circuit can do to electrical equipment (smoke, fire, and destruction). Electrostatic discharge (ESD) is an unseen (and sometimes unheard) force, created by humans, that is just as deadly to a computer.

The key to ESD prevention is to keep all electronic components and yourself at the same electrical potential. This usually means ground potential or zero volts. Maintain a habit of "grounding" yourself to the computer chassis whenever you attempt a repair. An ESD wrist strap is the tool most commonly used by technicians to prevent ESD.

What is a latent failure? What makes it especially troublesome?

This type of ESD problem occurs when a transistor junction becomes weakened. A transistor in this condition may pass all quality tests but, over time, will generate poorer system performance and eventually fail completely.

What is a catastrophic failure?

Catastrophic failure is the destruction of a part because of the heat generated during the mishandling and misapplication of a power source, cable, or test instrument.

When working with a computer, when is it acceptable to use an AC power supply that is not grounded?

It is never acceptable to use an AC power supply that is not grounded.

Chapter 14

Describe a basic sample toolkit for the computer professional.

The basic toolkit should include screwdrivers, a Torx driver, tweezers, needlenose pliers, chip removers, a tube for small parts, a can of compressed air, ESD tools, a multimeter, a flashlight, a nut driver set, and curved hemostats.

What is a Torx driver used for?

A Torx driver is used to remove the star-shaped screws found on some proprietary computers. (Sizes T-10 and T-15 should meet the needs of most computers.)

How many bootable floppy disks are needed for a computer professional's tool kit?

One bootable floppy disk is needed for every operating system that you will be working on.

You are only going to check the memory chips. Do you need to follow ESD (electrostatic discharge) safety practices?

Always use ESD safety practices.

SIMMs are available in two physical configurations. What are they?

SIMMs (single inline memory modules) are provided in two basic (physical) formats: a 30-pin and a 72-pin chip.

You have an extra 16 MB of RAM on a single 30-pin SIMM, and a friend has a computer and needs more memory. What do you need to check in order to determine if this memory module can be used on your friend's computer?

You first have to determine whether there are any 30-pin slots available, then check the bus width to determine how many you will need to complete the job. For example, if the machine is a 486, you will need four modules to complete the job.

What is parity? Can parity chips be mixed with nonparity chips?

Parity is used to check the reliability of data. Parity requires one additional bit (chip). Memory can be purchased with or without parity. Parity adds about 10 percent more to the cost of memory. You cannot mix parity and nonparity chips.

Can L1 cache memory be upgraded?

L1 cache is part of the CPU and cannot be upgraded.

Your client wants to install an internal modem. How would you determine whether this internal modem could be installed on your client's machine?

First, the machine must have an available expansion slot. Second, there must be available resources such as IRQ and an address.

A friend just got a bargain on a new Plug and Play sound card and wants to install it on her 486SX computer. Will it work?

It will probably work, but will have to be manually configured either through software or jumpers.

How do you determine whether to upgrade the CPU or install another motherboard?

First, you must evaluate the existing motherboard to see if it can be upgraded and then determine the highest CPU that you can use. Second, you must determine the needs of the customer, particularly whether the CPU upgrade will meet the customer's operational requirements.

What is the advantage of Plug and Play?

Plug and Play, the latest technology available for installing expansion cards, is an independent set of specifications developed by a group of hardware and software companies. This specification allows the user to make configuration changes with minimal adjustments. The user simply installs the card, turns on the computer, and uses the device.

What are the four requirements that must be addressed before installing a new drive in a computer?

Will the drive physically fit inside the computer?

Will the computer's BIOS and operating system support the size (storage capacity) of the drive?

Will the drive controller support the new drive?

Are there sufficient cables (data and power) to install the drive?

Chapter 15

What does DOS stand for?

DOS stands for disk operating system.

What was DOS created to do?

The original version of DOS was designed to support the operation of floppy disk drives.

Which version of MS-DOS is bundled with Windows 95?

The version bundled with Windows 95 is referred to as MS-DOS 7.0.

Describe the core operating systems within MS-DOS.

IO.SYS: This system is the interface between the hardware and the operating system code.

MSDOS.SYS: This system is the main operating-system code.

COMMAND.COM: This system is the interface between the user and the operating-system code.

What are the two MS-DOS startup files?

CONFIG.SYS: This startup file loads extra hardware and device drivers not built into the IO.SYS.

AUTOEXEC.BAT: This startup file loads terminate-and-stay-resident (TSR) programs selected by the user and sets up the environment variables such as TEMP and PATH.

Which MS-DOS command is used to determine the amount of free space left on a disk?

From the command prompt in the root directory, the MS-DOS command DIR or directory will return the list of all the files on the drive and indicate the amount of free space available.

Describe the difference between real mode and protected mode.

MS-DOS operates with a 1-MB memory limit. This is called real mode. Windows broke out of the MS-DOS 1-MB barrier by engaging 286-level protected mode (Windows 2.0). Protected mode Windows could address up to 16 MB of RAM. Although MS-DOS programs could run only in the first megabyte of memory, specialized programs were written that would run in (and only in) the extended memory controlled by Windows. Protected mode refers to using protected memory.

Windows provides a GUI for the user. What does "GUI" stand for? What is its advantage over the older MS-DOS system?

GUI stands for graphical user interface. MS-DOS used a text or command-line interface. With MS-DOS, you had to memorize and type commands. With a GUI interface, you work in a graphical environment and use a mouse with icons or menus to simplify tasks.

Describe the three kinds of fonts used in a Windows environment.

Windows provides three types of font files. Each font contains a complete character set for a particular typeface.

Vector fonts are designed as a set of lines drawn between two points. Each character represents a mathematical model that can be scaled to virtually any size.

Raster fonts are bitmap fonts made up of a set of dots. Each character or set of dots is "painted" on the screen or printer. Because each character requires separate data for each size, only limited scaling is possible.

TrueType fonts are made from an "outline" of each character. When printing (on the screen or on a printer), these outlines are filled in.

Name five settings that can be changed from the Windows Control Panel.

Many settings can be changed from the Windows Control Panel.

Some of these are Screen colors, Other desktop options (screen savers, wallpaper, and so on), Fonts, Printer, Keyboard, Mouse, International settings, COM port settings, Network settings, Date and Time, Sounds (used by the system), Drivers for hardware, and Multitasking and virtual-memory settings.

Which wildcard character can be used to replace a single character in a search string?

The single character wildcard is the question mark (?).

Chapter 16

Name three ways that Windows 95 differs from Windows 3.x.

Installing devices, managing memory, optimizing the system, and troubleshooting are handled differently in Windows 95 than in Windows 3.x.

What is Plug and Play? What is required for a component to be Plug and Play-compliant?

The ultimate goal of any computer user is to be able to simply plug any device into a computer, turn it on, and have it work. This is the concept upon which Plug and Play is founded. A well-designed Plug and Play system eliminates the need for jumpers, switches, and installation software.

The three requirements of Plug and Play are: a Plug and Play BIOS, a Plug and Play device, and a Plug and Play operating system (such as Windows 95).

Does Windows 95 still require MS-DOS?

Windows 95 does not require MS-DOS. MS-DOS is provided mostly for backward compatibility.

Which version of MS-DOS comes with Windows 95?

DOS 7.0 comes with Windows 95.

Is CONFIG.SYS required to install GUI drivers?

CONFIG.SYS is not required to install GUI drivers; however, it is required if you want to use any real-mode drives.

Why would you want to set the swap-file size in Windows 95?

The VCACHE that comes with Windows 95 is quite different from Windows 3.x in that the cache is "sized dynamically." As Windows needs more RAM, it takes away from the cache and vice versa. Unfortunately, the cache-sizing algorithms are very slow, especially when used with the swap file; therefore, the swap file needs to be limited in size.

What is the main difference between Windows 3.x and Windows 95?

Windows 3.x is basically an operating environment created to run on top of MS-DOS; its purpose is to provide a GUI and other features in order to run programs and manage files easily. Windows 95 is a complete operating system that includes an improved GUI as well as other useful features.

Why can't older versions of disk utilities be used with Windows 95?

Older disk utilities do not understand many of the improvements of Windows 95, such as long filenames.

After turning on the power to the computer, what is the first step in the boot-up process?

The first step in the boot-up process is to run the POST.

In which directory do you find the external MS-DOS commands?

MS-DOS external commands reside in the windows\command directory of the bootable drive.

What is FDISK used for?

FDISK for Windows 95 is no different than for Windows 3.x; it is used to partition hard drives. Windows 95 OSR2 and Windows 98 do give the option of using FAT32 file system instead of FAT16.

Define virtual memory.

Virtual memory uses disk space to simulate RAM. This hard disk drive space is called the swap file.

The Registry is composed of two binary files. Name them.

The two binary files that hold the Registry database are called SYSTEM.DAT and USER.DAT.

What is the difference between an MS-DOS session and MS-DOS mode?

An MS-DOS session runs inside a window in the GUI. Windows 95 has the new MS-DOS mode that allows creation of custom CONFIG.SYS and AUTOEXEC.BAT files for tough MS-DOS applications. MS-DOS mode exits the GUI—therefore, you might have to configure real-mode drivers to access hardware.

If you are running in MS-DOS mode and the CD-ROM does not run, what must you do to get it running?

You must create (or edit) the CONFIG.SYS and AUTOEXEC.BAT files to load the appropriate real-mode drivers for the CD-ROM. You will also need to run the MSCDEX.EXE application.

Do you need a .PIF file to run an MS-DOS program in Windows 95?

Windows 95 no longer creates .PIF files by using the PIF editor. PIF settings are created by accessing the Properties value that appears when an MS-DOS application is right-clicked.

What are the five steps of a Windows 95 installation?

The five steps are startup and system check; information collection; hardware detection; startup disk creation and file installation; and windows configuration.

Which version of Windows 95 uses FAT32?

Only the OSR2 version uses FAT32.

What is safe mode and what is it used for?

Safe mode starts Windows 95 with a minimum of drivers. This mode is considered to be the Windows 95 troubleshooting mode.

What are the three Registry backup tools provided with Windows 95?

The three primary Registry backup tools available in Windows 95 are: Microsoft Configuration Backup (CFGBACK.EXE), Emergency Recovery Utility (ERU.EXE), and REG files.

Chapter 17

In Windows 95, which Windows 3.x program was replaced by Windows Explorer?

Windows Explorer replaced the Windows 3.x File Manager—the more advanced Explorer is the better choice for computer professionals.

What utilities are provided for managing files in Windows 95?

Windows 95 uses two programs for managing files: My Computer and Windows Explorer.

How do you partition a drive in Windows 95?

Use the FDISK program that came with Windows 95 to partition hard disk drives.

What is the function of the Recycle Bin?

The Recycle Bin provides temporary storage for discarded or deleted files.

What is the System Monitor used for?

The System Monitor provides real-time reports on how different system processes are performing. It displays various functions using either a line graph, a bar graph, or a numeric graph.

What is the Resource Meter used for?

The Resource Meter is used to monitor the use of system resources in real time. When activated, it adds a small bar graph to the taskbar (in the notification area) that indicates the percent of free resources (based on the computer's total resources).

Loading which file will cause Windows 95 to report an appropriate version of MS-DOS to older MS-DOS applications?

With SETVER.EXE loaded, Windows 95 will report a compatible version number to your MS-DOS application.

Identify the four basic kinds of viruses and describe how they are transmitted.

File infector viruses attach themselves to executable files and spread to other files when the program is run.

Boot sector viruses replace the master boot record (or boot sector on a floppy disk). They write themselves into memory any time the computer is booted.

Trojan horse viruses appear to be legitimate programs, but when loaded, begin to harm or destroy the system.

Macro viruses are major nuisances. These viruses commonly infect Word documents. Attaching themselves as executable code to documents, macro viruses run when the documents are opened. (They can also attach to some kinds of e-mail.)

Your best protection is to acquire and use an antivirus program. Remember to keep it up-to-date as new viruses are created every day.

Chapter 18

Name the three basic elements required to create a network.

The three basic elements required to create a network are connection, communication, and services.

The primary benefit of a LAN is its ability to share resources. Name some of the other benefits of networking.

In addition to the ability to share resources, LANs are resilient, act as communication gateways, and facilitate electronic mail.

What is the difference between a peer-to-peer and a server-based network?

In a peer-to-peer network, each computer acts as a server or a client depending on the user's needs. Each user, or workstation, establishes its own security and determines which resources are available to other users.

In a server network, a central server (dedicated computer) manages access to all shared files and peripherals. This is a secure environment suitable for most organizations.

Name the three network topologies.

The three network topologies are star, bus, and ring.

What type of cabling do thin Ethernet and UTP cabling require?

Thin Ethernet uses a round BNC connector and UTP uses an RJ-45 connector (similar to a telephone jack).

What is the function of a network interface card?

Network interface cards (NICs) link the computer to the network cable system. They provide the physical connection between the computer's expansion bus and the network cabling.

Name the three main types of network cabling. What are their advantages?

Twisted-pair cable is very common, easy to install, and inexpensive.

Coaxial cable is found in two types: thin (ThinNet) and thick (ThickNet). When compared to twisted-pair, coaxial cable is the better choice even though it costs more. It is a standard technology and resists rough treatment and electromagnetic interference (EMI). Although more resistant, it is still susceptible to EMI and eavesdropping.

Fiber-optic cable is made of light-conducting glass or plastic fibers. It carries data signals in the form of modulated pulses of light. Although it is no less expensive (in both installation and cable cost) than twisted-pair or coaxial cable, it has advantages. It is immune to EMI or detection outside the cable. It supports very high bandwidths (the amount of information the cable can carry) and can handle thousands of times more data than twisted-pair or coaxial cable.

What is the purpose of network protocols?

A network protocol is a set of rules governing the way computers communicate over a network. In order for computers using different software to communicate, they must follow the same set of networking rules and agreements, or protocols. A protocol is like a language. Unless both computers trying to communicate are "speaking" and "listening" in the same language, no communication will take place.

Describe the functions of a router, a bridge, and a gateway.

Bridges work like repeaters but offer additional advantages. They can isolate network traffic or problems. The traffic within a segment will not be sent to the entire network unless its destination is in another segment. Bridges can also link unlike segments (Ethernet and token ring).

Routers provide interconnectivity between like and unlike devices on the LAN and WAN. Routers work like bridges, but can connect networks using different protocols and can select the best route from network to network based on traffic load. Routers route data based on factors such as least-cost, minimum delay, minimum distance, and least congestion. Routers are generally used to create a wide area network and to connect dissimilar networks.

Gateways provide as much interconnectivity and even greater functionality than routers and bridges do. A gateway usually resides on a dedicated computer that acts as a translator between two completely dissimilar systems or applications. Since a gateway is both a translator and a router, it tends to be slower than bridges or routers. Gateways also provide access to special services such as e-mail or fax functions.

What is the most widely used network protocol?

TCP/IP is the most widely used network protocol. It is the protocol of the Internet.

What is the difference between a LAN and a WAN?

A LAN is a local area network; it is usually confined to a limited space such as a building or a room. A WAN is a wide area network and can span long distances (even worldwide).

Your network is showing signs of reduced bandwidth. What is causing this problem?

This type of problem is called a bottleneck. A bottleneck on a system is the resource that limits the rate at which a task can be completed. If your task uses the processor, network and disk resources, and spends more of its time transferring data to and from the disk, you might have a memory bottleneck. A memory bottleneck might require adding more RAM.

What is an ISP?

An ISP (Internet Service Provider) provides the connection between dial-up (modem) users and the Internet.

Name some of the most common Internet domain extensions.

Here is a table of common Internet domain extensions. How many did you get?

.com	Commercial organizations
.net	Networks
.edu	Educational institutions
.org	Nonprofit organizations
.gov	US Government nonmilitary institutions
.mil	US Government armed services
.xx	Two-letter country code

What does URL stand for?

URL stands for Uniform Resource Locator, the address system used on the World Wide Web.

Besides A+ Certification, what other computer-related certifications are available?

Other certifications available are Novell CNN and CNE, or Microsoft MCP and MCSE.

Name the three main types of portable computers.

The three types of portable computers are laptop, notebook, and subnotebook or palmtop computers.

What is a docking station?

Docking stations (also known as docking ports) are specialized cases that allow entire notebook computers to be inserted within them. This allows the notebook to be connected to desktop I/O devices such as full-sized keyboards, CRT monitors, and network connections.

What is the purpose of PCMCIA cards?

In order for laptop and notebook computers to have the same degree of expandability that is associated with desktop computers, the Personal Computer Memory Card International Association (PCMCIA) established several standards for credit-card-sized expansion boards that fit into small slots on laptop and notebook computers.

Describe the different PCMCIA card types.

There are four types of PCMCIA cards:

Type I is the original computer-card standard and is now referred to as the Type I standard. These cards are used only for memory. Type I cards are 3.3 mm thick.

Type II cards support most types of expansion devices (like communication hardware) or network adapters. Type II cards are 5 mm thick.

Type III cards are primarily for computers that have removable hard disk drives. This standard was introduced in 1992. Type III cards are 10.5 mm thick, but they are compatible with Type I and Type II cards.

Type IV cards are intended to be used with hard disk drives that are thicker than the 10.5-mm Type III card.

How do you configure a computer card?

PCMCIA (PC-Card) is part of the Plug and Play standard. Plug and Play-compatibility means being able to add components without turning off or rebooting the computer. PCMCIA buses are not configured with jumper settings (because they don't have any) but with software.

What are the two kinds of displays found on laptop computers?

The two types of displays found on laptop computers are active-matrix and dual-scan.

Why is heat dissipation a concern in computer-chip technologies for portable computers?

In desktop systems, CPU heat is dissipated with the use of cooling fans housed inside the case. There is no room for this solution in a portable system, so manufacturers have addressed this problem in the packaging of the chip itself.

With the exception of Macintosh, what drives are standard in a portable computer?

Except for the size and packaging, hard disk drive technology is similar to desktop technology. EIDE drives are standard in portables, with the exception of Macintosh, which uses SCSI.

Chapter 19

What items should be included in a cleaning kit?

A cleaning kit should contain at least the following: lint-free cloth, cleaning solution, foam swabs, and antistatic spray.

Why is ESD dangerous to computers?

ESD (electrostatic discharge) will destroy electronic components.

Will a properly grounded computer help prevent EMI?

Yes, a properly grounded computer will help prevent EMI (electromagnetic interference).

Describe some safety precautions you can take to protect yourself from high voltage when working on a computer.

Never work above your skill level when it comes to safety! Working inside the monitor case should be left to a properly trained technician with the necessary tools to protect against high voltages.

The power switch on some computers, usually located on the front of the computer, uses 110 volts AC to turn the power supply on or off. If you are working on a computer and it is plugged in to provide proper grounding, this could present a hazard.

What type of fire extinguisher is used for an electrical fire?

Type C fire extinguishers are used for electrical fires.

How do you clean a keyboard?

To clean a keyboard, use a hand-held vacuum to remove dust from the small crevasses.

How do you clean a laser printer?

To clean a laser printer, complete the following steps:

Remove the toner cartridge.

Vacuum dust build-up and excess toner from the interior.

Clean the laser printer's rollers using a damp cloth or denatured alcohol.

Clean the paper-handling motor's gear train, using a swab.

Apply light oil to the gears, using a swab.

Distribute the oil throughout the gear train.

Clean the writing mechanism thoroughly, using compressed air.

If possible, wipe the laser lens with lint-free wipes to remove fingerprints and stains.

Clean the corona wires using a swab dipped in alcohol. Be careful not to break any of the strands; if they are broken, your printer will be rendered useless until they are repaired.

Give one example of a recyclable item that requires special disposal.

Examples of recyclable items that require special disposal are batteries, toner and cartridge kits, circuit boards, chemical solvents, and monitors (CRTs).

Why is a toner cartridge easy to recycle?

Often the manufacturer provides a prepaid shipping box to return the cartridge.

What is a material safety data sheet?

When purchasing or using any kinds of chemicals (for instance, cleaners) be sure to look at the MSDS (material safety data sheet). This form describes the nature of any chemicals manufactured. It includes generic information about the chemical makeup and any recognized hazards of the product (along with what to do and who to call if there is a problem).

Chapter 20

Name five ways to stay on top of your profession.

Five ways to stay on top of your profession are to: keep learning; network with others; take advantage of opportunities to connect with your peers through professional groups and trade shows; practice your skills; and read widely.

How and where can you obtain technical support?

The unlimited free technical telephone support that we once took for granted is being replaced by support offered through e-mail and the Web. This means that increasingly we are expected to get the job done without free direct phone support from the original equipment manufacturer (OEM). Technical support is out there, but it must be used wisely to be cost-effective.

What are the four categories of tools used by computer technicians?

Four categories of tools used by computer technicians include hardware toolkit, software toolkit, spare parts, and access to a technical library.

Which files are essential for a software toolkit?

The bare minimum software toolkit should include: ATTRIB.EXE; DEFRAG.EXE; EDIT.COM; EMM386.EXE; EXPAND.COM; FDISK.EXE (.COM); FORMAT.EXE (.COM); HIMEM.SYS; LABEL.COM; MEM.EXE; Memmaker; MSCDEX.EXE; MSD.EXE (.COM); QBASIC.EXE; SCANDISK.EXE; SHARE.EXE; SIZER.EXE; SMARTDRV.EXE; and SYS.COM.

What are the five phases of troubleshooting?

Phase 1 is to define the problem.

Phase 2 is to identify the cause.

Phase 3 is to make the repair.

Phase 4 is to confirm the repair.

Phase 5 is to document the incident.

How important is record keeping?

Good recordkeeping is essential if you are to become a success at your profession. Recordkeeping is the process by which you keep track of which techniques worked and which did not work. In short, it becomes your experience database. Good records will save you valuable time in the long run.

What are the three levels of technical support?

Level 1 is to provide local support by assigning a knowledgeable person onsite to address minor problems.

Level 2 is to provide telephone support.

Level 3 is to provide on-site support.

Why is it important to standardize equipment in large organizations?

Standardization of equipment in large companies reduces the number of spare parts required and simplifies installations.

What are the four stages to follow when you receive a service call?

The four stages of a service call are the greeting, the description, the interview, and the closing.

How would you deal with a difficult client or coworker?

If the individual needs training, ensure that they have information about available courses.

If the individual is a coworker, speak to the person who supervises them and identify their training needs.

If the individual is a client, gently suggest that it would be beneficial to obtain specific training.

Send the client a memo or instruction sheet to follow. Save the instructions for future use.

Dealing with technophiles (or those who think they are experts) can be a challenge. The best option is to listen carefully and make the individual part of the solution, not part of the problem. Remember, they came to you for help.

In a corporate setting, form an advanced users group and give participants responsibility for finding solutions to issues. Ask coworkers (or users) who constantly complain about trivial problems to put all complaints in writing. Keep their notes as part of your records.