I am doing my research to get my mac pro. I have a question for video cards when it comes to gaming. I am not sure at this time if I should get a single 8800 or dual 3870's. I plan on having a Vista or XP bootcamp so I can still have access to newer games (Bioshock, COD4 etc). I know the 3870's will use crossfire when I boot that way, but is it faster then a single 8800 GT? Has anyone seen benchmarks for these 2 setups in OSX and in Windows via bootcamp?