Do you have any reason to use the 6800k in this build? For a few dollars more you can get the 8320 which is a huge performance boost.
I dont need it. Just thinking about it. :) But thats a good point . No need to buy a apu when you can get a 8 core instead.
actually no what your not thinking about is the APU uses 750mbs of vram that means you have a total of 750mbs of video ram adding a extra card doest add that ram you still have 750mbs and that is far to low for 1080p resolutions.
Then there is the fact 60% of games run worse or dont run at all with crossfire - then you ARE not useing crossfire you have the extra headaches of running hybrid crossfire + you over spent on a video card you are going to run at less than 1/2 speed for crossfire.....as i allrady sead pointless to runn a 7750 for APU-hybrid crossfire.