Buffalo & Erie County Public Library: Computer Training Programs

the single large printed circuit board located just off the enclosure's base
holds the majority of a computer's processing power
as a minimum, a motherboard contains the system CPU, clock/timing circuits, RAM, cache, BIOS, serial port(s), parallel port and expansion slots
it is the motherboard more than any other element of the PC that defines the performance

Other Motherboard Components

System BIOS

"Basic Input/Output System"
provides an interface between the PC hardware and the standarized operating system
allows the operating system to interact with the memory and the various devices and drives in the system
initial instructions for processor to start devices, read from hard drive
Be Very Careful in the BIOS

Expansion Card Slots

allows video, sound, and floppy disk and hard drive controller circuitry to be disabled from the motherboard

CPU (Central Processing Unit)

brain of the computer
processor rests on the motherboard
responsible for processing each instruction and virtually all of the data needed by the computer
the type of CPU limits the PC's overall processing power
you can't just place any CPU in the CPU socket and expect the motherboard to work

Memory (RAM: Random Access Memory)

the CPU can get information from any location in the memory in less than a millionth of a second
memory is what the CPU looks through in order for the software to accomplish anything
the CPU never looks directly at the information on your hard drive, floppy disk, or your CD-ROM

Cache Memory

traditional RAM is much slower than a CPU: the CPU must insert pauses to catch up
cache is a technique of improving memory by keeping a limited amount of frequently used information in a very fast cache RAM
if the needed information is found, the CPU reads the cache at full speed. performance is improved because less time is wasted
by making the cache larger, it is possible to hold more frequently used data

Bits

computers work with very small bits of information called bits which have to be combined into larger clusters to be of much use
the basic clusters used by most computers is 8 bits and is known as a byte
memory size is measured in bytes and of course, more is always better
since computers need huge numbers of bytes to do anything useful, the measure of a megabyte (one million bytes) is used

Drives

Places to store, read, and/or write data. There are two types of drives: internal and external. The external drive bay allows a drive to be mounted facing the outside of the computer. Examples are floppy, CD-ROM, CD-R, DVD, PC Card, and tape drives. Hard drives are mounted on a internal bay. A typical desktop PC offers two external and 2 internal bays.

Hard Drive

huge, fast, reliable, and quiet storage mechanism
standard equipment on all PCs and are the preferred boot device for even the largest operating system
typically uses one light to indicate drive activity

Floppy Disk Drive

provides permanent, removable, limited storage for your computer
capable of storing up to 1.44 MB on a 3.5" disk
uses only one light to indicate drive activity

Zip Drive

3.5" drive capable of storing up to 100MB on a single zip disk
combines magnetic and optical storage technology
looks similar to a floppy disk drive
some PC manufacturers now include Zip drives as standard equipment in their systems

CD-ROM Drive

standard equipment in all modern PCs
uses a load/eject button, a volume control (to adjust CD audio) and a single activity light
one optical disk can store up to 650 MB of programs, data, or other media

CD-R Drive

allows you to record your own CD
uses a load/eject button, drive activity light, and volume control
uses a second activity light to show when the drive is writing

DVD Drive

DVD disks can offer up to 17 GB of storage on a single disk the size of a CD
are backward-compatible with almost all existing CD-ROM standards
ideal medium for the distribution of audio and video multimedia and incredible amounts of data
uses a load/eject button, a volume control (to adjust CD audio) and a single activity light

PC Card Drive

supports the easy transfer of files between laptop and desktop systems
looks like a 3.5" floppy drive but the card opening is thicker and narrower
doesn't work like a traditional drive as it is entirely electronic. There are no moving parts except for the electrical card connector and a simple card ejection mechanism
the mechanical lever ejects the PC card, and a single light is used to indicate drive activity

Tape Drive

offers a significant amount of storage capacity using relatively inexpensive tape media
usually limited to system backup chores as the tape devices are slow, hot and noisy
uses 2 lights; one a power indicator and another as a drive activity light

Expansion Boards

Video Card

performs the job of a cable box or the antenna and tuner on your TV
takes the information the motherboard tells it to display and generates the signals that the monitor understands

Sound Card

the adapter which gives your PC the ability to play or record voice and music
essential part of every PC used for educational, game and multimedia applications

Network Card

the adapter which lets your PC communicate on a network

Serial and Parallel Ports

PC communication is accomplished through the use of parallel or serial ports

Parallel Ports

allow the PC to drive printers
operate hard drives, CD-ROM drives
implemented as a 25 pin female connector

Serial Ports

used for online communication
one or two ports on a PC
newer versions 9 pin D type male connector

TOP...