Yeah the main bottleneck seems to be the videocard. Ram is probably enough.

But seeing as I'd like to goto a 7600GT, I might as well go with a new MB, processor and some new Ram as well, since the AGP version of a 7600GT is a lot more expensive (think I saw about 40-50 euro) then a PCI-e one.
I've had this setup for a long time (think about 4-5 years), so it's really time for an upgrade.

Anyway, when I get my new stuff (should be end of Nov) I'll post again how well it plays.