As long as the motherboard has a PCI Express (PCI-E) slot it should be fine. Get one that has at least one 16x PCI-E slot for graphics. OR, one with two 16x slots with SLi / Crossfire support if you plan to add another graphics card in the future.
Assuming you'll be getting a 8800GT, if you can stretch your budget a little, also consider the newer breed of cards - the nVidia 9800GTX, & ATI: HD 4850 or HD 4870 in particular.
What's the rest of your proposed spec may I ask? G