If ya go AMD, get a Barton 2500+ Athlon XP. And cooling and sound as a factor? Get the Thermalright SLK-600.
It looks like a hunk of metal, right? Well, that's what it is. Copper, to be exact. There isn't a fan on it. No sound whatsoever! And guess what...that's right, this heatsink
works better than 80% of the heatsink fans out there. It retails for about $45.00 US dollars.
Ya get the cooling you need, no sound, and a badass Athlon XP 2500+ all under $150.00.
-Lasereth