The System Unit

Shaylee Johnson (377)

Mrs. Porter

TBE 1700

May 22, 2007

The System Unit

The System unit is a case that houses the electronic components of the computer used to process data. Although many systems units resemble a box, they are available in many shapes and sizes. The case of the system unit, sometimes called a chassis, is made of metal or plastic and protects the internal electronic components from damage. All computers have a system unit (Alvarez 102).

Components of the system unit include the processor, memory modules, adapter cards, drive bays, power supply, ports, and connectors. The processor interprets and carries out the basic instructions that operate a computer. A memory module houses memory chips. An adapter card is a circuit board that provides connections and functions not built into the motherboard . A drive bay holds a disk drive. The power supply allows electricity to travel into the computer.

On a personal computer, the electronic components and most storage devices reside inside the system unit. Other devises, such as a key board, mouse, microphone, monitor, printer, speakers, scanner, and digital camera, normally occupy space outside the system unit (How to Use a Computer). On a desktop personal computer, the system unit usually is a devise separate from the monitor and keyboard. Some system units sit on top of a desk. Other models, called tower models, can stand vertically on the floor.

To conserve space, an all-in one computer houses the system unit in the same physical case as the monitor. On notebook computers, the keyboard and pointing devise often occupy the area on the top of the system unit. The display attaches to the system unit by hinges. The system unit on a PDA (personal digital assistant) or handheld computer usually consumes the entire device. On these small mobile devices, the display is part if the system unit, too.

Works Cited

Alvarz, Juan. Understanding Computer Basics: Stepping Toward Literacy. Chicago: Martin Publishing, 2005.

How to Use a Computer. Shelly Cashman ®. Course Technology. 3 Aug.2005. www.scsite.com/wd2003/pr2/wc1.htm.