Hello, I see a price drop and could buy two 5770 cards and cf them, Would be a good thing to do instead of buying one 5850. Aslo what could of psu are we talking.
More about5770cf 5850
In terms of performance, 5770s in CrossFire would perform similarly to a 5870.So I would suggest that you go for the 5770 if they are cheaper.A good 650W PSU is the minimum for running two of these in CrossFire.
HD 5770 XFire is about the same as the HD 5870.
That's assuming the game takes advantage of XFire.
I would get the 5850, despite the maturity of CF and SLI there is still a significant number of issues, either with old games or new games.