I have two PowerColor 5770s in crossfire right now, and I'm debating upgrading my computer from Phenom II to a Sandy Bridge setup.
My main question is, should I go for a 6870 or a 6950? I've been trying to find a review that compares the performance of 2 5770s to other setups, but I'm having a hard time. From what's I can find, they perform similarly to a single 5850, so a little worse than a 6870 on average. I'm mostly looking to switch platforms and "reset" my upgrade path rather than get a huge graphics performance boost, but I don't want to hinder myself by cheaping out on the single GPU. I also recall that the 69xx series scaled significantly better than the 68xx series when it comes to crossfire.
i agree with boris, but you might want to just do the videocard for now. in a month bulldozer will be out and might look like a better option for a new system and if not sandy bridge will likely be cheaper to compete.