Get an AMD, not an Intel. All the new Athlon64's support AMD's new cool 'n quiet technology, and it's great. Sometimes the CPU fan even spins down completely! Intel made a huger error somewhere with their latest Presscott CPU core, because it's HOT! It easily runs up to 122-140 F, while an AMD runs at about 95-105°F. Intel themselves have also already acknowledged the problem and are working on a solution, but it won't be here for another year or so.

Just make sure you choose a motherboard that is running of an nVidia nForce4 chip for the best performance with an AMD 64. With this chipset, an AMD also outperforms and equally graded Intel, at much, much lesser temperatures...

(and this coming from someone who absolutely hated AMD for their low quality products in the past! But I do mean in the past, because AMD has really learned from their mistakes!)