Just bought a Mac Pro. It arrives in a few days as I had it customized. It comes with a rather lackluster NVIDIA GeForce 7300GT video card. I just bought a NVIDIA Geforce 7900GT card for my PC. Can I easily swap the cards? Are they compatible in both machines? I'm also hoping the video card drivers already installed in the Mac will work with the card I am swapping out as they are both within the NVIDIA Geforce series.