A lot of people are discovering that their pc's overheat when running 100% all the time.

Some of us got in to distributed computing projects because it helped us test stability on computers that had been modified for speed. Mod geeks learned that getting rid of excess heat was essential to really working a computer.

Therefore, Cooling 101:

1) air has got to move through your computer and out to cool it. Ideally there should be fan pulling in low front and blowing out in the high back (in a tower configuration and employing air cooling... which is the standard).

2) bigger heatsinks and bigger fans usually cool a cpu better.

2a) a faster fan cools better too, but usually annoys people, so a bigger fan is usually better.

3) computers build up dust after a few months (conditions depending). Carefully vacuuming out the dust from intakes and heatsink fins often helps... and in the case of older computers it's absolutely essential. Be careful with the static electricity though.

4) if you own a laptop, there are addons you can get that sit under the laptop and act as a big heatsink fan. Placing your laptop on a bare, metal table would be nearly as helpful. The wood and 'composite' surfaces (laminated fiber board) that make up most tables are very good at reflecting heat back IN to your laptop.

5) the motherboard in most computers has a northbridge... a chip that handles data moving around the cpu, ram, and agp bus (a 'bus' is a data circle). Most motherboard manufacturers don't put heatsink fans on this chip. Helps if you do.

6) if you want to get into it in a big way then you can mod your computer for watercooling (a big project) which will almost never overheat. A smaller investment (with a desktop box) involves replacing your cpu with a mobile version of the cpu. Both Intel and AMD make mobile chips. They're designed to draw less voltage so they put out less heat.