You might consider upgrading to an X1950PRO 512mb AGP, a beefier PSU and OC'ing your 2.8C a bit. That would probably get you another year and you could re-use the new PSU in your next build and probably sell the Pro for close what you paid for it.
I've got a similar system to yours (P4E at...
http://www.chumbo.com/Info.aspx?id=304966
It seems to be a PCI 6200. Should be faster than any FX5700 or 9100 Thats the only place I've ever seen em. Assuming its not a misprint. (The box seems to say PCI as well)