Originally Posted by Ben the OCer
Yes, the HD5570 supports Crossfire. Often low end cards don't need a Crossfire bridge which you can misunderstand as not supporting Crossfire. The brand does't matter, they just have to have the same GPU. Here is a review from Tweak Town that compares Crossfire HD5570, single HD5570, and HD5670:
A single HD6670 GDDR5 would be a good option as then you wouldn't have any Crossfire hassle for whether it works for the games you play. It seems that Crossfire HD5570 performs pretty good so if a second one is cheap enough it's definitely an option.
Thanks, that review helped. I got a couple follow ups, though. All the cards I have access to have GDDR3 memory, not GDDR5, so I'm thinking of going the crossfire way since it seems to give good results. But, should I get the HD 5670 or is that potentialy more troublesome to be worth it? Than setting it up with the same card I got (HD 5570), I mean.
I mainly want it to play the new World of Warcraft expansion, and I've read that game works with crossfired cards. I'm assuming GDDR3 HD 6670 is clearly below the other options but if it isn't I could use the heads ups there too