ok im Building a new system i already have 2 4850's and im going to go with the MSI 790FX-GD70 with 4 way CrossFire and i was waiting to know if it would be better going with 4 4850's or 2 5850's or just the 5870
2 5850s!! according to some random 4850 quadfire benchmarks I read yesterday, crossfire with two 4850s is faster than 4 in every game except for Unreal Tournament 3. a 5850 isn't too far behind a 5870 so crossfiring 5850s is the best option.