My second build. Your thoughts please?

[Mizzou]

I'm using a Corsair HX850 in my AMD rig and am very satisfied with it. Also have a Corsair 1000HX in my Intel system, no problems there either.

 

[Leeky]

The SPU's (shaders) work in tandem in CF obviously. The lower memory is not a concern with AMD cards should the op go for a triple monitor setup. AMD frame rendering changes from AFR to 'supertiling'.( they render in 32 x 32 pixel sections of the screen, rather than alternating frames) All of the GPU's have access to the total buffer . This can be a limiting factor for Nvidia SLI setups (AFR only) but is a nice option for AMD cards.

As for the 2560 x resolution, here is a lengthy benchamark review
http://www.techpowerup.com/reviews/ATI/Radeon_HD_6870_CrossFire/1.html

I clearly had that totally wrong then. I always assumed the HD69xx would trump the HD68xx when we started looking at 2560x or higher resolutions.

Thanks for explaining dude