There are many sources of heat that can raise the temperature in your PC. No, I'm not talking about the Tabasco sauce you dripped over your keyboard when you ate that bowl of chili at your desk, and no, I'm not talking about that Pamela Anderson (or Ricky Martin poster, depending on your taste) above your desk. Heat can come from external and internal sources. Let's take a look at those different heat sources, identify them and see what can be done to eliminate the problem.

External Heat Sources

Direct Sun exposure

Is your PC sitting near a window where it is exposed directly to sun light? Then move it. That pale beige color of the case is natural and won't tan no matter how long it sits in the sun. Move the PC into a spot where it is safe from sun rays.

Heating Systems

Is your PC sitting next to a radiator? Is there a floor heating vent next to it? Do you have a space heater under your desk right next to your PC? Then move it.

Other Heat Sources

Is your PC sitting in between your stove, the microwave, the TV and/or your stereo? Then move it. They are all producing heat which your PC won't like.

Lack of Ventilation

Is your PC crammed into the corner between your desk and the wall like a cork into a bottle neck with no room for air circulation? Then move it. Air is the main source of cooling, but without it your PC will overheat. Move it out of any confined spaces and give it about a foot all around for proper air circulation.

Dirt

I've opened up some PC cases that were beyond disgusting. I've found ants, spiders, spider webs, twigs, leaves and dust bunnies the size of basketballs inside some PCs. Dirt clogs up the few holes in a case that supply air and can cause fans to stop working. As part of your preventative maintenance, get a few cans of compressed air (be sure to get the one that doesn't harm the ozone layer) and blow out the inside of your PC regularly.

Jason Barrett
http://www.computing-forums.com