processor

[b1gapl]

I got the 3700+ oced to 2.5GHz and a 7600GT and plays everything on high.

 

[Camshaft]

I would have gone for am2 but your card is probably agp and you have ddr1 RAM already

 

[Apokalipse]

if you don't want to upgrade your video card and RAM (because of PCI-E and DDR2), then a socket 939 upgrade will be good.