Location and Care of a Personal Computer

Properly maintained, a personal computer (PC) will withstand extensive use. Most computers have a user's manual which includes a section on physical maintenance, and this should be read carefully. Safety and operating instructions should be followed and kept for future reference, and all warnings should be heeded. The common sense points outlined below can help prevent damage and improve the utility of a computer.

Location of Personal Computers

A PC needs a stable base with good air circulation, such as a table, cart, shelf or desk able to support the weight of the computer. If set up on its side, a stand that will keep it from tipping should be used. Follow the manufacturer's instructions to avoid injury to a person or damage to the equipment.
Use a surge suppressor or uninterruptable power supply (UPS) to buffer the electrical supply to a computer. A power surge or brown out could damage it or the data.
Slots and openings in the case are provided for ventilation and to prevent overheating, and should never be blocked or covered. If the PC is on a carpeted floor, a stand should be used to raise it slightly so that air can flow underneath it. Books or other items should not be stored in such a way that they cover the ventilation slots on the computer.
The computer should be kept at room temperature and not be placed where it will get intense exposure to sunlight or other heat sources such as radiators, heaters, stoves, etc. Do not place or use the computer near water - avoid such things as sinks, wash basins, bath tubs, open windows, etc.
The monitor and keyboard should be placed directly in front of the user. The monitor should sit at a comfortable viewing distance (usually 50-60 cm from the eyes) and should be at or slightly lower than eye-level.
Equipment should be positioned at right angles to windows to minimise glare and screen reflections. It is often necessary to provide window blinds whilst avoiding the situation where blinds are down and lights are switched on permanently. Semi-translucent blinds stop glare from the sun but let in some light.
Avoid moving computers when they're running. Move them only when powered off.

Cables

Never insert or remove cables when a PC is powered on, since this can cause an electrical short circuit. If a cable becomes loose, power the PC down before re-attaching the cable. Keyboard commands can be used to save work before doing this.
Cables must not touch heaters, and must not be placed where they could be tripped over.
Make sure that there is some slack in the cables attached to the computer. If they're stretched taut a port may become damaged, or the connection between cable and computer may not work consistently. Taut cables are also more likely to come loose. Longer cables for keyboards, power connections, and other connections are available from most computer suppliers.
Long cables, such as those for a network connection, may become crimped against the wall or under heavy furniture. Make sure nothing is resting on the cables, and take care when moving furniture that these cables aren't caught and damaged.

Cleaning

A computer will become dirty over time, and should be cleaned to keep its components performing well. Always turn off and unplug the computer before cleaning it.
To clean the screen, keyboard, case, or mouse, dampen a cloth with antistatic foam cleaner and wipe the computer clean. (Always spray the cleaner on the cloth and then use the cloth to wipe the computer. Never use liquid cleaners or aerosol cleaners directly on the computer.)
To clean the mouse, remove the cover over the track ball on the bottom (it twists or slides free) and remove the track ball. A cotton bud dampened with foam cleaner can be used to clean between the keys of a keyboard, to remove dirt from the rollers inside the mouse or in other tight places.
Ensure that all cables are re-attached properly before powering the PC back on.
Avoid opening the monitor's case, as a severe electric shock can result from touching monitor components.

Adapted from Stanford University's PC care page in the light of later research and experience.