I started and continue to update this build on another forum, but I thought I'd post it here as well.
Planned parts (January 2018):
CPU: 2xIntel Xeon Platinum 8168 (24/48 Core, total 48/96) (arrived)
Motherboard: ASUS C621E SAGE (arrived)
Graphics: 2xNvidia Titan XP (somewhere)
Memory: 384GB Crucial DDR-2666 RDIMM (arrived)
O/S Storage: Intel Optane P4800X 750GB (arrived)
Fast Data Storage: Intel Optane P4800X 750GB (on-the-way)
Main Data Storage: 8xIntel DC P4500 4TB (or 8xIntel DC 4600 4TB if I manage to work out how to mount 8 PCIE cards neatly) (still planning out)
PSU: Corsair AX1600i (arrived)
Case: Phanteks ENTHOO ELITE Grey (arrived) - This case is yuge, shipping weight is 50kg. It's even bigger than my old Lian-li V2120X. The case comes with its own hard-case.
Radiators: 2xEK Coolstream CE 420, 1xEK Coolstream CE 560, 1xEK Coolstream CE 140 (Optional)
CPU blocks: Some crap I bought from taobao
GPU blocks: EK Nickel+Acetal
Pump/Res: 2xEK, single line
Tubing: Hard front, soft back, all black.
Fans: NF-A14 industrialPPC-2000 PWM or NF-P14s redux-1500 PWM (depends on which one looks better to me)
Fittings: Primochill+EK fittings
Fan controllers: Lamptron 6CH/30W + Corsair Commander
Fan hubs: Phanteks + Silverstone
I selected the 8168 based on the much higher all-core frequency of 3.4Ghz. Although the 8180 has 28/56 cores, the all-core frequency is only 2.9Ghz. I'm not putting much hope in to the motherboards OC capabilities. It can only do BCLK and in most cases, getting a stable +10Hz on a single CPU is already considered decent. I'd imagine getting something similar with dual cpu's would be outstanding.
The motherboard only has 4xU.2 NVME, the rest will come from an ASUS Hyper M.2 x16 card mated with 4x M.2 to U.2 adapters. Technically, the motherboard should support PCIE bifurcation, but since I don't have a test bench setup yet, this remains to be proven.
The taobao cpu blocks only come with a rectangular retention plate (for boards like Supermicro). The ASUS board uses a square retention plate, I have to find a solution for this later on. I have 2U Dynatron B13 HSF's on the way in the meantime.
Some motherboard pics:
Intel Xeon Platinum 8168
Intel Optane P4800x 750GB
Nvidia Titan Xp's