Ge t a good power supply.
Athlons are notorious for liking power,
and if you're gonna do lots of processor intensive stuff,
like encoding mp3's all day, you wnat good power.
Plus if you buy a good power supply, it's quiet.....
cheapo's are LOUD.
I've got an ennermax in my machine Athlon XP 1600,
adjustable speed fans, nice feature.