Power Supply: CORSAIR Professional Series Gold AX850
Initially I was tempted to get the AX860 to take advantage of the Platinum efficiency, but it seems many users are experiencing noise problems. I also considered the AX860i but don't see much value in monitoring the PSU via software, plus the Cross Link software appears not be fully ready yet for Windows 8.
Cooling: CORSAIR Hydro H80i. I'm also considering the Noctua NH-D14 SE2011 to avoid the potential (small) risk of a leakage and the potential kinks of the new Corsair (e.g. software compatibility with Win 8), however the Noctua's size is monstrous and I won't have access to the DIMMs. According to the Noctua website, this cooler is compatible with both the mobo and RAM I have chosen. Also I have seen pictures of it installed in the Define R4 case therefore it fits.
Alright, z79 build is not recommended mainly because quad channel ram has no practical performance increase anywhere, and definately not to fps; z79 does not support trim in raid 0 configurations, z77 does; It's boards are more expensive. The only reason I see in going z79 is for the six core processor, specifically for businesses that use programs that can utilize 6 cores to render things quicker thus making money faster. Unless this is making you money, don't do it. We can do a nice crossfire build for 1500ish. Take a look.
This is with SLI 660Ti(660 sli is the best price/performance which would drop price by 100$), h100i(Drop this for a hyper212 80$ saved), highest rated case on newegg(Could drop this for a mid-tower/the case you provided 50$ saved), and raided SSD(And of course going with 1 ssd would bring price down 135$) All changes made brings price down 360$ equaling a 1500 dollar build as I mentioned above. For a x79 alternative to this,
And the same cutbacks above can apply here. We change the cooler for a hyper, 660Ti for 660, 1 SSD instead of raided(No trimm support when raided on x79) and finally the case change the total price would be 1980$
Either way you go these builds are bad ass. If you are worried about performance on SLI 660/660Ti here are 2 benchmarks:
I would really not bother with sli 670s/80s because the fps difference between 660ti is 10, and 20 respectively. Granted you did say this wasn't for gaming but the general horse-power of the setup still applies; sli 660/Ti's will get the job done.
On a closing note, any one of these builds leaves you with 700+ for multi-monitor/speaker/headphone/sound card/keyboard/mouse&pad or just pocket change. And the case to end all cases will be sold on the 18th of March@369.99 http://www.corsair.com/900d It really is beautiful. For air-cooling or water-cooling setups, it ends all cases. It's closest equal is the Cosmos II @ http://www.coolermaster.com/product.php?product_id=6792
I hope I helped you out a bit, GL with your build and whatever you ultimately decide on.