Thanks for the reply
I guess what im asking is I can get another 285 for about 5o pounds which is a lot cheaper than getting say a 570. What single card would two 285 s be comparable to?
Other than a GTX590 I don't think there is any single card that is going to be more powerful than a pair of GTX285's. If DX11 is not a big deal for you then I would say go for it, I'm currently testing a GTX580 and I can tell you now that whilst it's quite powerful it's not as mind blowing as some would have you believe.