|All you had to do was go to the HP site & look it up. Here's what it states:|
Supports AMD Athlon 64 X2 (up to 4800+) and Sempron (up to 3200+) processors"
Hopefully the RAM you bought is DDR400 & not DDR333. HP tended to install DDR333, presumably because it was cheaper at the time of assembly. You take a performance hit because of it though.
BTW, here's a copy of the motherboard manaul: