Quote Originally Posted by Solus Corvus View Post
Maybe at release. But not after the crossfire improvements in drivers released since then. I have been using a 5970 since shortly after release and it has improved substantially. In games that scale properly across 2 gpus and aren't cpu bound a 5970 is about 45-65% faster then a 5870. The average was dragged down by many games without proper 5970 support in the driver, but many were added in more recent drivers. Crossfire/SLI scaling isn't great, but it isn't 40% with proper profiles either.
Last time HD 4870 and HD 4870 X2 were reviewed using Cat. 9.5, the difference was 46% on average. That should be around a year after the initial release, so plenty of time.
I don't doubt, that HD 5970 is doing better now, but across many games in different resolutions and settings, the average won't be much better. Definitely not good enough to justify going dual GPU.