Depends on how much you're spending on the 6790. I got mine for $89 (after MIR) a few weeks ago and I am tickled pink with it. If you are spending $150 for a 6790, I would say get a 6850 for that $150. I see you have the PC AX6790 penciled into your rig, probably paid $110 and are getting Dirt with it if you are getting from Newegg, pretty good deal. My intention is to get another 6790 in the next couple of months and Crossfire them. I am guessing you are already aware that the 6790 and the 6800s use the same BARTS LE GPU. The 6790s scale above 90% in Crossfire, whereas the 6850s scale at around 80%. Result: two 6790s perform about the same as two 6850s. Here is a good breakdown of the 6790 in crossfire
. This was written 6 months ago when the 6790s were new and cost within $10 of a 6850- it didn't make much sense to go with a 6790 at that price, but now the 6790s have dropped down to about $100 and make them about the best value around for budget GPUs.
This chart is for Metro, which is about as heavy on GPU as BF3. You can see that two $100 6790s run within 1 fps of two $150 6850s, and both of them Crossfired do better than a single $400 6970. With your nice mobo, you might as well shoot for a crossfire setup at some point.Edited by Jagged_Steel - 10/30/11 at 7:15am