Computer System Unit Parts

The Computer System Unit

The system unit is the box-like case that contains major computer’s electronic components which many people erroneously refer to the CPU. Inside this box like case you will find devices like the power supply, the drives, fan, connectors, and the motherboard to mention but a few. Note that in most cases the monitor also known as display, keyboard and mouse will not be found inside the system unit layout.

The system unit is sometimes called computer chassis, cabinet, box, tower, enclosure, housing, system unit or simply case.

Parts of the System Unit in Computer

The system unit of any desktop computer houses many components. These are some of the major components you are going to find inside your system unit. If you think of checking these components, make sure you power off your computer and disconnect it from the mains.

Then locate the top lid of your system unit and remove it so that you can access the inside of your base unit. Be careful not to mess with your components if you are not very familiar with them. Before touching your components, take care of the ESD precautions.

Computer Base Unit

Computer System Unit
Computer System Unit | Source

The Computer Motherboard

The motherboard is sometimes called the system board or main board. It is the main circuit board of a microcomputer. The motherboard contains the connectors for attaching additional boards. All the computer components connects in one way or the other with the motherboard.

Typically, the motherboard contains the CPU, BIOS, memory, mass storage interfaces, serial and parallel ports, expansion slots, and all the controllers required to control standard peripheral devices, such as the display screen, keyboard, mouse and disk drive.

When you are reading about motherboards you can not fail to come across the term motherboard form factors which describes its general shape, the type of case and power supply it can use, and its physical organization (layout of the motherboard).

A Computer Labeled Mainboard

A Labeled Motherboard
A Labeled Motherboard | Source

Hard Disk Drive

A hard disk drive is a high capacity non volatile magnetic data storage media with a volume (disk) which is usually non-removable.

Data is magnetically read and written on the platter by read/write heads that float on a cushion of air above the platters.

A Hard Disk Drive

Hard Disk Drive
Hard Disk Drive | Source

Floppy Disk Drive

Short for floppy disk drive (FDD), it is a disk drive that can read and write floppy disks although they are obsolete nowadays.

Floppy disk drives have been replaced by the USB flash disk drives.

Floppy Disk Drive

Diskette Drive
Diskette Drive | Source

Power Supply Unit

The power supply unit (PSU) is used to convert AC current from the mains supply to the different DC voltages required by various computer components.

Standard power supplies turn the incoming 110V or 220V AC (Alternating Current) into various DC (Direct Current) voltages suitable for powering the computer's components.

Power supplies are quoted as having a certain power output specified in Watts, a standard power supply would typically be able to deliver around 350 Watts.

The more components (hard drives, CD/DVD drives, tape drives, ventilation fans, etc) you have in your PC the greater the power required from the power supply.

ATX Power Supply Unit

Power Supply Unit
Power Supply Unit | Source

DVD-ROM, DVD Writer, CD-ROM Drive

It is a high capacity optical data storage device with a removable disk, it writes data onto or reads data from a storage medium.

A CD-ROM drive may be connected to the computer via an IDE (ATA), SCSI, S-ATA, Firewire, or USB interface or a proprietary interface.

CD ROM Drive

A CD Rom Drive
A CD Rom Drive | Source

How To Identify The Components Inside Your Computer

Your Opinion

Have you ever opened a desktop computer system unit?

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© 2010 Patrick Kamau

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Comments 14 comments

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Patkay 3 months ago from Nairobi, Kenya Author

Thank you Ziel for the visit and comment. I am happy that you have found the content of this hub useful. Keep reading!


ZIEL 3 months ago

THIS IS WONDERFUL ,THANK you for the information


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Patkay 4 years ago from Nairobi, Kenya Author

eunice, you are welcome. Thanks for reading and commenting.


eunice 4 years ago

thaks for the knowledge


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Patkay 4 years ago from Nairobi, Kenya Author

Thanks Mohamed Dhidha. I like enlightening people about computers. There is a lot to learn from the computer world.


Mohamed Dhidha 4 years ago

The information was presented in a very good format, very interesting and very helpful. Thank you so much.


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Patkay 4 years ago from Nairobi, Kenya Author

You are welcome chrysann Evans. It my pleasure to find that you are contented by what I am offering here.


chrysann Evans 4 years ago

thanks for your help


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Patkay 5 years ago from Nairobi, Kenya Author

Thanks Abrabanj, for going through this useful information. There is a lot to learn in the computer world.


Abrabanj 5 years ago

A nice and very good expression system unit


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Patkay 5 years ago from Nairobi, Kenya Author

Thanks AMUZU for reading and commenting.


AMUZU 5 years ago

well done


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Patkay 5 years ago from Nairobi, Kenya Author

Thank you stasheen brown for dropping by, check more of my hubs for a lot of helpful information.


stasheen brown 5 years ago

thank you for all the information. very helpful :)

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