I ran 2, 6970's in crossfire for a long time. They ran everything at 60+ FPS once I figured out the sweet spot with setting up the crossfire profile for each game. It may have been some work, but I like to tweak and I always saw improvements with my crossfire setup.
That said, I grow tired of my 2 970's. SLI runs without any tweaking, but that's about it. I may have performance out of the box, but it's nothing like my old crossfire setup. The new 300 series isn't what I hoped so I will be putting water blocks on my MSI's. Still won't see much of a difference since the watt's is max'd already on stock voltage (just increase cpu/mem MHz), but I have not been impressed with the intel/NVidia monopoly. I build anything, run everything. If it's the right price I'll make it quick, but the game has become tiresome.
Edited by SIN Deacon, 23 August 2015 - 09:47 PM.