You should have no problem even adding a PCI-Express 2.0 card to your motherboard, since its a socket AM2, or 939 to fit your CPU. I know of only a couple common motherboards made for those sockets that ever had an AGP option for graphics. It's likely you're compatible with ATi as much as you are with NVIDIA, though i'd check your motherboard model on google. Also, avoid purchasing a 9800gx2 card unless you are certain your motherboard has built in SLI compatibility, as it's 2 cards running SLI in a single slot. (Not certain if this applies, I haven't worked with single GPU boards since AGP went extinct)