A lot of people find the heat output from their PCs to be a problem. Here's the solution. I did it on Windows 2000 using a mobile Barton on an old GA-7DX Gigabyte motherboard
If you have a mobile AthlonXP (or probably an unlocked desktop part, I don't have one so I can't be sure) you can set up your desktop PC to change its multiplier as processor demand increases. Just like PowerNow on a laptop.
Here's how.
First download and install the PowerNow driver from www.amd.com.
Now go to
http://crystalmark.info/?lang=en' ">http://crystalmark.info/?lang=en and download CrystalCPUID. Its a zipfile and freeware.
Extract CrystalCPUID files to a directory and run CrystalCPUID. Play around to get used to it, you can change the multiplier and the core voltage. I use a tool like Taskinfo from www.iarsn.com to watch the processor (also free). You set up multiplier management in CrystalCPUID from the menu. Specify both the voltage and the multiplier for each of three loads (min, mid & max) and the threshold at which each is triggered.
To run CrystalCPUID in the systray use a command line. Mine is CrystalCPUID /P1 /CQ /HIDE /F24
Put this command line in your startup folder for all users.
There, easy! Now the PC will run a low speed and cool most of the time - I have mine set to 800MHz and 1.1v. When the demand increases it goes straight to 2GHz at 1.45v and stays there for at least 5 secs when it drops, first to 1.2GHz and then back to 800MHz.
You can change parameters easily by just clicking on the systray icon which brings up the main dialog.
The CPU temperature is dramatically lower, less than 10'C more than the system temp.
Enjoy!