1. The system bus and I/O bus carry four different types of signals throughout the
computer. Which of the following are the signals? (Choose all that apply.)

a. Data
b. Power
c. Control
d. Adapters
e. Address


2. Which of the following are considered expansion slots? (Choose all that apply.)

a. PCI
b. FireWire
c. AGP
d. USB


3. Which of the following can you use with SCSI (Small Computer Systems Interface)?
(Choose all that apply.)

a. Hard drives
b. Scanners
c. Laser printers
d. DVD-ROMs
e. A dot-matrix printer


4. Which of the following are in the ATX family of motherboards? (Choose all
that apply.)

a. ATX
b. Mini-ATX
c. FlexATX
d. ATX and Mini-ATX only
e. None of the options provided is correct


5. Which of the following are considered integrated I/O ports?

a. Serial port
b. Parallel port
c. USB port
d. PS/2 mouse and keyboard
e. Audio port
f. Ethernet port
g. All of these options are correct


6. Which one of the listed processors was the last slot-based processor designed
by Intel?

a. Celeron
b. Core 2 Duo
c. Pentium D
d. Pentium III


7. Which of the following processors was the first dual-core design by AMD?

a. Athlon 64 X2
b. Athlon
c. Duron
d. Sempron


8. Which of the following best describes hyperthreading?

a. Overclocking your CPU
b. Processing two execution threads simultaneously
c. Having more than one processor
d. None of these options is correct


9. Before you remove the processor from the motherboard, what device should
you remove first?

a. Power supply
b. RAM chip
c. Heat sink
d. Thermal compound


10. You have been dispatched to a client’s computer. You have decided that the
processor is overheating. Which of the following steps can you take to help with
the air flow around the processor?

a. Blow it out with compressed air
b. Remove the heat sink from the CPU
c. Place it on a surface covered with old newspapers or waste paper
d. Clean off the old thermal paste and reapply a small amount to the
processor
e. All of these options are correct


11. Which of the following are causes of overheating? (Choose all that apply.)

a. Fan failure
b. The power supply fan is too large
c. Incorrect heat sink
d. Incorrect processor


12. To connect speakers to the sound card, which of the following must you use?

a. 1/2-inch jack
b. 1 1/4-inch jack cable
c. 2/3-inch jack cable
d. 1/8-inch mini-jack cable
e. None of these options is correct

If you’ve never opened a computer before, it can be pretty overwhelming. This
section helps you get started with practical advice on how to

■ Open the case
■ Protect your system against electrostatic discharge (ESD)
■ Connect internal and external data cables
■ Install a PCI card


Opening the Case of a Desktop PC



Look at your system manual for case opening instructions, particularly if you have
a retail-store system made by HP, Dell, or other major vendors. Depending upon
the type of case you have, you might need to remove just one or two screws, or
maybe a handful. If you’re opening the case to gain access to the motherboard, you
might need to do more than just take the cover off the system.
So-called “white box” systems are usually fairly straightforward to open because
they use case designs made for user access instead of low cost. Figure 2-5 shows
the rear of two typical cases used by white-box computer dealers or as replacement
cases. The computer on the left has a single screw holding the covers in place. After
this screw is removed, the top panel must be removed before the side panels
can be removed. The computer on the right uses four screws per side to hold the
side panels in place, but the side panels can be removed without removing the top
cover. The right-hand side panel can even be swung out and latched back into
place for faster card and drive installation.

What makes a computer a computer? After all, some furniture stores put 3D cardboard
facsimile computers on computer desks so you can see that the furniture really
will hold a computer. But, what is it about a real computer that makes it
different than the cardboard phony?

Real computers contain a variety of components and subsystems, including

■ Storage devices
■ Motherboards
■ Power supplies
■ Processors/CPUs
■ Memory
■ Display devices
■ Input, multimedia, and biometric devices
■ Adapter cards
■ Ports and cables
■ Cooling systems

This section describes the components of a desktop PC and contrasts the feature of
a desktop with those of a laptop, or notebook, computer. Front and Rear Views of a Desktop PC
Many of these components are visible in the front and rear views of a desktop computer.

Fron View of Normal Tower CPU

Rear View of Normal Tower / Desktop CPU

1. Power supply fan
2. Case fan
3. Empty expansion slot without slot cover
4. Empty expansion slot with slot cover
5. TV tuner card
6. Motherboard diagnostic lights
7. USB port
8. Power supply on/off switch
9. AC power connector
10. PS/2 keyboard port
11. PS/2 mouse port
12. HDMI audio/video port
13. VGA video port
14. DVI-D video port
15. IEEE-1394a (FireWire 400) port
16. Ethernet (RJ-45) port
17. 1/8-inch mini-jack audio port cluster

Test yourself online choosing the following MCQs for Hardware IT essential Questions....

1. You are working on a computer. Which of the following are considered essential?
(Choose all correct answers.)

a. Motherboard
b. CPU
c. Memory
d. Video card
e. A scanner


2. Which of the following devices might be found on the front or back of a computer?
(Choose all correct answers.)
a. Activity lights
b. Power switch
c. USB ports
d. None of these options are correct


3. Which of the following can cause a desktop computer to fail? (Choose all
that apply.)

a. Overheating
b. Loose add-on cards
c. Drive failures
d. Adding more memory


4. Which of the following are the most commonly used Windows operating systems?
(Choose the three best answers.)

a. Windows XP
b. Windows 2000
c. Windows Vista
d. Windows 98


5. Which of the following can be used in your day-to-day work on a standard
Windows computer? (Choose the two best answers.)

a. CHKDSK
b. toopath
c. Disk Defragmenter
d. ifconfig


6. Which of the following is the first thing you should do when replacing a PCI card?
a. Shut down the system and unplug the power
b. Open the case
c. Open the package and sit it beside the computer
d. Purchase the device


7. Which of the following steps is important to perform when opening the case to
access the internal parts of a computer?

a. Check your system manual
b. Get out the screwdriver
c. Check for ESD
d. None of these options are correct


8. Which of the following can help in preventing ESD? (Choose two.)
a. Touch the unpainted metal of the chassis
b. Wear sneakers
c. Remove the power supply
d. Wear an antistatic wrist strap


9. How do you identify the cable that connects to the floppy drive?

a. It is flat.
b. It is the longest cable.
c. There is a twist at one end.
d. None of these options are correct.


10. How do you attach the VGA cable to the video card to prevent it from losing
connection?

a. By snapping it into the video port with both thumbs
b. By using the locking arm mechanism
c. By using a torx screwdriver
d. By turning the thumbscrews


11. Which of the following types of hardware resources do both onboard and addon
card devices use? (Choose all that apply.)

a. IRQ
b. DMA
c. Memory
d. I/O port


12. What is the process of bypassing the CPU called?

a. Direct Memory Access
b. Memory Leak
c. Task Manager
d. Device Manager

Data is constantly being transferred within a computer and between computers.
But how much data, and how fast is it being computed? Data transfer is known as
bandwidth, which specifies how much data is being sent per second. The speed at
which data is computed is known as Hertz, which also dictates the frequency used
to transfer data.



Bandwidth
Other than bits and bytes and their multiples, probably the second most significant
concept to understand about computer measurements is bandwidth, also known as
data transfer rate. Bandwidth refers to the amount of information that can be sent
or received through a computer or network connection in one second. This can be
measured in bits (with a lower case b) or bytes (with an upper case B). For example,
the bandwidth of a USB 1.1 port running at full speed transfers a maximum of 11
megabits per second (11 Mbps, notice the lower case b), while the bandwidth of a
USB 2.0 port running at high speed is 480 Mbps, and a user might download 300 kilobytes (300 KB/s, notice the upper case B) of data per second. Or an expansion
card that goes into a PCI slot could transfer a maximum of 266 MB/s.
Bandwidth measurements like this are used for measuring the performance of serial,
parallel, wired and wireless network connections, expansion slots (PCI, PCIe,
and AGP), hard disk interfaces (PATA and SATA), and multipurpose device interfaces
(SCSI, USB, and FireWire). It defines the amount of information that can
flow through the computer.
Information flows through the computer in many ways. The CPU is the central
point for most information. When you start a program, the CPU instructs the
storage device to load the program into RAM. When you create data and print it,
the CPU instructs the printer to output the data.
Because of the different types of devices that send and receive information, two
major types of data transfers take place within a computer: parallel and serial.


Parallel Information Transfers
Parallel transfers use multiple “lanes” for data and programs, and in keeping with the
8 bits = 1 byte nature of computer information, most parallel transfers use multiples
of 8. Parallel transfers take place between the following devices:
■ Processor (CPU) and RAM
■ Processor (CPU) and interface cards
■ LPT (printer) port and parallel printer
■ SCSI port and SCSI devices
■ PATA /IDE host adapter and PATA/IDE drives
■ RAM and interface cards, either via the CPU or directly with direct memory access
(DMA)

Although a byte represents the basic “building block” of storage and RAM calculation,
most measurements are better performed with multiples of a byte. All calculations
of the capacity of RAM and storage are done in bits and bytes. Eight bits is
equal to one byte.


Measurement                                      Type                             Number of Bytes/Bits
                                                       D=Decimal                                                             
                                                       B=Binary                                                                
                                                                                                                                       

Bit                                                   1/8 of a byte

Nibble                                             1/2 of a byte

Byte                                                 8 bits                                                                 

Kilobit (Kb)                                     D                                     1,000 bits
                                                        B                                     1,024 bits (128 bytes)

Kilobyte (KB)                                  D                                     1,000 bytes
                                                        B                                     1,024 bytes               

Megabit (Mb)                                  D                                     1,000,000 bits
                                                        B                                     1,048,576 bits (131,072 bytes)

Megabyte (MB)                               D                                     1,000,000 bytes
                                                        B                                     1,048,576 bytes                       

Gigabit (Gb)                                     D                                     1,000,000,000 bits
                                                        B                                     1,073,741,824 bits                   

Gigabyte (GB)                                  D                                     1,000,000,000 bytes
                                                        B                                     1,073,741,824 bytes                

Since the development of the first personal computers (PCs) more than 30 years
ago, many terms such as bits, bytes, decimal, binary, and hexadecimal have become
part of common language. However, these terms are not always used correctly. This
section helps you understand what these terms and numbering systems mean and
how they relate to the PC technologies you will be studying in future chapters.

Three numbering systems are used in computers: decimal, binary, and hexadecimal.
You already are familiar with the decimal system: Look at your hands. Now, imagine
your fingers are numbered from 0–9, for a total of 10 places. Decimal numbering is
sometimes referred to as base 10.

The binary system doesn’t use your fingers; instead, you count your hands: One
hand represents 0, and the other 1, for a total of two places. Thus, binary numbering
is sometimes referred to as base 2.
The hexadecimal system could be used by a pair of spiders who want to count: One
spider’s legs would be numbered 0–7, and the other spider’s legs would be labeled 8,
9, A–F to reach a total of 16 places. Hexadecimal numbering is sometimes referred
to as base 16.


Decimal Numbering System
We use the decimal or base 10 system for everyday math. A variation on straight
decimal numbering is to use “powers of 2” as a shortcut for large values. For example,
drive storage sizes often are defined in terms of decimal bytes, but the number
of colors that a video card can display can be referred to as “24-bit” (or 224), which
is the same as 16,777,216 colors.

Binary Numbering System
All data is stored in computers in a stream of 1s (on) and 0s (off). Because only two
characters (0 and 1) are used to represent data, this is called a “binary” numbering
system. Text is converted into its numerical equivalents before it is stored, so binary
coding can be used to store all computer data and programs.
Table 1-2 shows how you would count from 1 to 10 (decimal) in binary.


Decimal  0  1    2    3     4      5     6      7      8      9      10
Binary    0  1   10  11 100   101 110  111 1000 1001 1010


Because even a small decimal number occupies many places if expressed in binary,
binary numbers are usually converted into hexadecimal or decimal numbers for
calculations or measurements. Binary numbers are also the basis for bits and bytes:
a single binary value is represented by a bit, and eight bits equals a byte.