So... I took the time to configure this super beast. It's crazy what you ccan get as DDR3 transfers over DDR4. Honestly, we never did reach the peak of what we could with DDR3, and as such I feel as if it is bottlenecked because of it. Originally I had my mindset on an FX 9590 with this rig, but a 4820k will definitely outperform It. To those who ask why in the world I didn't go for a 5820k I have this to say: unless you are a true enthusiast, you do not want to bottleneck your rig when you first build it, by not maxing the RAM out. In this case DDR4 is way overpriced... Anyways here it is. I'm not going to be building it, just nothing better to do:
http://pcpartpicker.com/p/qgZ3sY
Yes you could subtract one of the 970s and possibly fit a 5930k in there, but once again 32gb of DDR4 is nearly double the price of 3.
I don't really get what you mean by bottlenecking it by not maxing RAM out? You won't use anywhere near 32GB of RAM unless you are editing absolutely massive 4K video files.
Do not get a 4820k. It is kinda crap tbh. You said it will definitely outperform a 9590? Not so much actually. In synthetics the 9590 is actually faster. (10285 vs 9861 according to cpubenchmark.net) and Logan even claimed that the 8350 was beating his 3820 (pretty much the same as a 4820) in most of the tests he did. It will only really excel in single threaded performance. So look at your workload. Personally I think the Socket 2011 quadcores are worthless and I believe Intel thinks the same because they got rid of them. The 6 core 5820 will be much faster than either the 9590 or 4820.
The motherboard you chose is meh. Not the best but okay and a good price. I wouldn't expect much overclocking on though.
The RAM. 32GB? I'm not really sure what you're going to be doing with this rig but unless it is 4K video editing (which the 4820K will kinda suck at) you don't need it. Additionally RAM speed is kind of pointless as well. While there are some advantages in productivity they aren't massive and in games there is no benefit to high speed RAM what so ever. You are paying more for a bigger number. Sorry.
The ADATA drive is okay. I'd much prefer a 840 Evo/Pro or preferably 850 Pro. But again depending on your application you may want to run multiple smaller SSDs in RAID. This is preferable especially if you are using them as scratch disks.
The HDD is okay. I have had bad luck with the Hitachi "Deathstars." I am leary of any drives over 1TB tbh. A WD Caviar Blue or Black would be a better bet. Again multiple drives in RAID may be a better idea.
Okay the GPUs what? What exactly is the purpose of this build? Gaming? Then I would definitely not recommend three GPUs. The scaling is terrible. Especially at lower resolutions and the narrower memory bus seems to nerf the Maxwell cards at higher resolutions. I would recommend preferably one single more powerful GPU or two more powerful GPUs. So one or two 980s. Or maybe even an AMD card if your applications prefer dat OpenCL. They will also be cheaper. If you are doing serious work then maybe a FirePro or Quadro would be a better bet here. But IMO three GPUs are silly. Especially in that case you chose which doesn't have the best airflow.
Your PSU is cutting it close too. 850W won't give you much room to expand.
I just have a feeling you could do a lot better than this for $2500.
Most of the time it is actually slower. The only real reason you would go to the 4820 is because you want the PCIE lanes and other features of X79 but can't afford the 4930k.
Get a 4790k and two 980s. Would be faster and cheaper.