Computer Hardware - What Are the Bits Called and What Do They Do

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Computer hardware - What are the bits called and what do they do.

A computer consists of the following parts:

 Main Memory  Case with Power Supply,  Monitor  Keyboard  Mouse,  Motherboard with CPU  Multi-IO card (usually built in to motherboard)  Video card  Sound Card  Floppy disk  Hard Disk.

1) Main memory.

This consists of both read only memory (ROM) and random access memory (RAM).

All computer programs and data must be completely loaded into RAM before they can be used. The amount of RAM will determine the maximum size (biggest) program that can be run. The more RAM a computer has the larger the computer program that can be run. Note however that all programs or data which are held in RAM are lost when the computer is switched off. These programs must be loaded back into RAM before they can be used again the next time the computer is switched on. A typical modern home computer will have (roughly) anything from ______to ______megabytes.

ROM is a special type of computer memory. It holds small programs which are usually only enough to allow the computer to load in larger programs from disk to RAM when the computer is first switched on. The benefit of ROM memory is that the program is not lost when the computer is switched off. The drawbacks of ROM are that the programs must be placed in ROM in the computer factory. The program held in ROM cannot be changed. To update the program you must replace the ROM memory in the computer. A modern computer will have about 0.1 megabytes of ROM memory. 2) Memory Sizes:

A bit is the standard smallest piece of information that a computer uses. Bit is short for 'binary digit'. A bit can be in only two states, usually called on or off (1 or O).

Byte. (B)

A byte of memory is a group of 8 Bits. The computers main memory ROM and RAM is divided into bytes. Each byte is given a unique number to identify it, numbered 0,1,2,3,... etc. This number is termed the address of the byte. This is enough memory to hold one letter of text

Kilobyte (K).

1 Kilobyte is 1024 bytes. This is a unit of measure used for computer memory and computer disks. This enough memory to hold ______

Megabyte (M).

1 Megabyte is 1024 Kilobytes. This is a unit of measure used for computer memory and computer disks. This is enough memory to hold ______

Gigabyte (G).

1 Gigabyte is 1024 Megabytes. This is a unit of measure used for computer memory and computer disks. This is enough memory to hold ______

Terabyte (T)

1 Terabyte is 1024 Gigabytes. This is a unit of measure used for computer memory and computer disks. This is enough memory to hold ______3) Hard disk.

This is used to store programs long term. Programs stay on the hard disk even when the computers power is switched off. Programs must be loaded from the hard disk into memory before they can be used. The larger the hard disk the more programs that can be stored on it. Hard disks vary in size from ______to ______. Hard disks are the fastest way to load programs into RAM. Hard disks are sometimes called fixed disks because they are fixed inside the computer’s case and cannot generally be moved from machine to machine, unless the machine is specially modified. Hard disks are so called because the disks are made from hard metallic or plastic materials.

4) Floppy disk.

These can be used to store programs long term. These disks are small and portable. They can therefore be used to move information from computer to computer. Floppy disks are so called because the disk material is made from a soft floppy plastic. Floppy disks are

Still called floppy disks even though they are sometimes enclosed in hard plastic cases.

Floppy disks load information much more slowly than hard disks and they do not hold as much information, usually only about ______

5) Tape drive

Computers can use tape drives for long term storage of programs. Tape drives can hold large numbers of programs. They can hold between ______and ______of information. But they are slow to operate and are thus generally only used nowadays to duplicate the information on a hard disk so that it can be recovered to a different hard disk in case any of the data on the hard disk becomes damaged or lost.

6) CD-ROM

These are like-read only hard disks. The ROM part stands for read-only memory. They are small portable CD-disks which can be moved from machine to machine. CDs can be read at about the same speed as hard disks. CD-R disks can only be written to with special equipment and once written to they cannot be re-used. CD-RW disks can be reused, but the CD-RW disks cannot always be read reliability in all computer CDROM drives. CD’s usually can hold about ______. They are usually used to hold large programs or databases which can be read into RAM for use. Because they are read only however the computer is required to have a hard disk to be used for storing temporary information while the CD is being used. 7) Network cards

Network cards can be used to link computers together with electrical cable. Computers can quickly pass large amounts of information back and forth to each other down this cable. Networks can be used therefore to allow computers to share resources such as hard disk, printers, CD-ROM drives etc. The most common type of network card is an Ethernet network cards. These commonly come in two speeds, slower 10 Base T and the faster 100 Base T.

9) Multi IO card.

This is an IO card incorporating a floppy disk controller card and Hard disk controller card. It connects the computers motherboard to external devices, either inside the case for hard and floppy disk and outside the case via serial and parallel communications ports to printers mouse etc. These cards are come built in on all modern motherboards and are only needed on older computers such as 286, 386 and 486 computers.

10) CASE.

This is a case which holds the motherboard and all cards and disks. These usually come complete with power supply and are available in two standard forms AT and ATX.

11) Video Graphics Card.

This is the card which allow the motherboards to communicate with the computer screen. The video card will usually have its own RAM in addition to the computers RAM. This video RAM is used to store picture for display. The more Video RAM you have the more dots (pixels) and colors you can display.

12) Monitor (the screen).

This is the computer screen. You must make sure that the computer screen you use is able to display the resolution and colors that the computers video card will supply. A monitor which can display at least _____ X _____ dots and ____ colors is said to be VGA (Video Graphics Array) standard. Monitors which can display more dots are described as SVGA (Super VGA).

13) Sound Card. Not all computers have a sound card. With a sound card a computer can play music or synthesize sounds. Without a sound card the computer can only make simple beeping sounds. The most common type of sound card is the Creative labs sound-blaster. Any card which is Sound-blaster compatible sound card can play music and synthesized sounds.

14) Motherboard with CPU and CO- PRO .

This is the main board inside the computer. Mainboards come in two standard forms, AT and ATX, each of which requires a different case type. The mainboard holds the CPU (central processing unit) which actually does the computing. The more powerful the CPU the faster the computer. There are several different models of CPU which can be found inside an IBM PC. These CPUs evolved over many years and they therefore run at different speeds. As a rule of thumb, each new model of CPU runs about half as fast again as the older model types. The main manufacturer of IBM pc CPUs has historically been Intel. However other companies such as AMD and Cyrix also make IBM PC CPUs which are compatible with the Intel models that they are listed with in the table below. The table lists each family of processor from the 80286 to the Pentium III. The 80286 is the slowest listed and the Pentium III is the fastest listed.

80286, V30 80386, AMD 386 80486, AMD 486, Cyrix 486 PENTIUM, K6, M1 Pentium II, K62, M2 Pentium III (IV), K7

Additionally CPUs of the same model can run at different speeds (anything from ______to ______MHz). The higher the MHz the faster the processor.

Motherboards come in two standard forms _____ and ______each of these will require a matching case and power supply.

Some older motherboards have an optional extra computer chip fitted called a math co processor. This extra chip can work with the CPU and help it do mathematical calculations. If this chip is present the CPU can run programs that require mathematical calculations much more quickly. Most 486 and all newer chips have these math co- processor chips built in, and therefore modern motherboards no longer have a separate math co processor socket.

15) Mainboard configuration CPU Voltage.

You must always ensure that your mainboard is set to the correct voltage for your CPU. To do this find the CPU core voltage which is usually written on the back of the processor and set the mainboard jumpers to that voltage. You will find the jumpers setting clearly marked in the manual that accompanies you mainboard.

CPU Speeds:

CPU Speeds are set by a combination of two factors on the mother board. The Mother board speed and the clock multiplier.

Most main boards will use jumpers to specify these settings.

Firstly set the jumpers for the main board speed that you want to use. These usually vary from 66 to 100 MHz.

Then set jumpers to say how many times faster than the mainboard the CPU should run . Option usually vary from 1.5 to 5.5 times.

For example a 200MHz Pentium computer could be set to a 66Mhz main board speed an a 3.0 X clock multiplier = 198 MHz.

Or a 450MHz Pentium could be set to a board speed of ______MHz and a clock multiplier of ______= 450MHz.

16) Keyboard.

This plugs into the computer motherboard and is the usual way in which the user will give instructions to the computer. There are three main keyboard connector standards these are AT, PS/2.and USB The PS/2 standard is the smaller of the two round keyboard ports that are typically found only on most computers.

17) Mouse.

This is a pointing device which can be used to operate the computer with only minimal use of the keyboard. Mice can commonly are connected via _____ or _____ or _____ ports on the computer.