This is actually about 6 months old and a little out of date. I have currently changed to a totally air cooled system and my GPU setup has entirely changed but I had the pics and this may be of interest to some people.
This is a workstation PC, primarily used for 3D motion graphics using Cinema 4D and Octane renderer. (for those interested, it hits well over 300 in octane benchmark) I also do some game dev in Unity 3D, video editing and general Adobe CC use and of course, gaming.
I'll do a quick run down of the interesting parts and try to explain my rational.
Case Gorgeous case by cooltek, the EU resellers of the jonsbo line (rosewill in the US I think). It's like a daddy version of the nCase, which I have pictured for comparison. (stay tuned for a mobile workstation build in that) This case is really compact, comparable to many mATX cases in size yet able to accommodate masses of hardware, and 8 PCI slots, perfect for me. I really appreciate the understated, clean design but there's also a windowed version if you're a fan of that.
CPU I needed 40 PCIe lanes with the highest clock speed. I wasn't concerned with core count as my GPUs do most of the heavy lifting. This fit my requirements perfectly.
Motherboard I wanted something very reliable that could potentially accommodate up to 4 GPUs. This fit the bill nicely.
RAM Capacity over speed. Nice reliable RAM, no need personally to spend more on anything faster. Will probably upgrade to 64GB soon as I'm starting to push the limits of 32GB with certain simulations.
Storage 750 is my boot and applications, really fast, perfect. Samsung m.2 is a scratch disc. Samsung 500GB is for all my current projects and resources I need to reference regularly. Everything else is on my NAS. Samsung 1TB, Steam library. A man has too have his priorities.
PSU Needed something very reliable and able to power a butt load of GPUS.
Silverstone Card reader Nice little find. Also has a couple of SSD mounts which I utilised as it made cable management easier. I know that it's position is not the most accessible but it doesn't bother me as I'm not a professional photographer and only need an SD card reader every few months, but I do need it and it's nice to have an inbuilt solution that's out of the way.
GPUs This is obviously not geared towards gaming. These cards were picked with CUDA performance in mind. Titan Z is still the best single card for Octane and at £750 on eBay this has been a great workhorse of a GPU. (I actually recently sold it for £860) the 6GB 780s were there for extra rendering power and I needed the 6GB to handle all the textures and 3D scene data. This wasnt too bad in terms of noise but the temps did consistently hit 83ºC on almost all cards so eventually I ended up completely changing my GPU setup that I will detail in another build post! In terms of CUDA rendering this machine ripped through anything at insane speeds and helped me hit deadlines I wouldnt have been able to meet otherwise. So in that regard the build was a success. Although I personally found it too noisy and too hot to put up with for too long.
If anyone is insterested I now have two 980tis (windforce xtreme) that stay really quiet and really cool. I am also in the process of building an eGPU build to provide the extra rendering horsepower when those tight deadlines arise.
EDIT: NO SLI BRIDGE? DAFUQ I've already had one comment about this so I thought I'd save the pain and address it here. A) There is actually internal SLI on the titan Z. B) With regards to the 780s Octane prefers the cards to not be in SLI. It treats each GPU as a separate CUDA compute device so it actually sees 4GPUs with this build. Having anything in SLI does not improve CUDA performance it only introduces complications. Not having the cards in SLI also lets me freely toggle GPUs on and off for rendering depending on what else I need to do. So when gaming with this build I used the titan Z in SLI. Otherwise no SLI. Hopefully this is clear!