Anytime I enable crossfire on the R9 290x my frames per second drop considerably (15-20fps) in all games that I have tried. I get micro stuttering as well as sound stuttering until I disable both crossfire and vsync.
I was using Catalyst 13.xx but just installed the latest 14.1 beta 1.6 and the issue persists.
In single card mode I get 60-80fps in most games, Battlefield 4, Planetside 2, Final Fantasy 14, etc. Soon as I enable Crossfire its choppy and runs at 15fps. Is AMD even looking into these reports as I have been lurking for months on this issue but now I decided to make an account and post as well.
I have yet to be able to use Crossfire at all with these cards and feel like I wasted $550 by buying a second one. I am still waiting for AMD to support their product but im starting to think I just need to get a refund and go back to nvidia...
Windows 7 64bit
Asus P8Z77-v CrossfireX
R9 290X in Crossfire