If you think you may go to crossfire in the not too distant future and can/are willing to spend the extra, 2 5870s are better than a 5970. That said, the one card takes up less space and uses less power, if I remember correctly. There is also less heat. I have the 5970 Black from XFX and love it. When you get up that high, a few frames/sec probably won't be noticeable. I don'r recall how the 5850 compares, but there are a few reviews that should list results comparing those various cards as singles and in crossfire. Good luck with your choice and enjoy!
