It should work with it. Your power supply should be sufficient, but don't expect to be able to play current games above low settings. You'll be able to hit medium on some undemanding titles assuming your at 1280x1024 or lower resolution.
eta: if you state your price range somebody can probably recommend a better card than the 8600gt.
eeta: he has a PCI-E slot, but only 305W on his PSU.