lyinch

Hey, I plan to build a (multi-GPU) deep learning workstation. It should be upgradable (replace individual components) and extendable (add components). I have no idea about current hardware trends so feel free to take it all apart. I need prices for Switzerland.
 
PCPartPicker Part List
CPU: AMD Threadripper 2920X 3.5 GHz 12-Core Processor  ($449.98 @ Amazon) 
CPU Cooler: Deepcool CASTLE 240EX 64.4 CFM Liquid CPU Cooler  ($120.99 @ Amazon) 
Motherboard: Asus ROG ZENITH EXTREME EATX sTR4 Motherboard 
Memory: G.Skill Ripjaws V Series 64 GB (4 x 16 GB) DDR4-3200 Memory  ($266.99 @ Newegg) 
Storage: ADATA XPG SX8200 Pro 1 TB M.2-2280 NVME Solid State Drive  ($149.99 @ Amazon) 
Storage: Western Digital Red 4 TB 3.5" 5400RPM Internal Hard Drive  ($116.99 @ Adorama) 
Storage: Western Digital Red 4 TB 3.5" 5400RPM Internal Hard Drive  ($116.99 @ Adorama) 
Video Card: Zotac GeForce RTX 2080 Ti 11 GB Blower Video Card (2-Way SLI)  ($1612.98 @ Amazon) 
Video Card: Zotac GeForce RTX 2080 Ti 11 GB Blower Video Card (2-Way SLI)  ($1612.98 @ Amazon) 
Case: Phanteks Evolv X ATX Mid Tower Case  ($177.99 @ Amazon) 
Power Supply: Corsair Professional 1200 W 80+ Platinum Certified Fully Modular ATX Power Supply  ($299.99 @ Amazon) 
Total: $4925.87
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2020-02-06 15:53 EST-0500
 
CPU
For multi-GPU usage I ideally have enough PCIe lanes. Theadripper 2nd Gen is cheap and supports enough lanes compared to the 3950x. While I can't upgrade to 3rd gen, I can always upgrade to the 2990WX which should last me another few years after the upgrade. 
 
MoBo
The same argument as for the CPU is done for the motherboard. The motherboard should fit the sTR4 socket and contain enough PCIe lanes to fully utilise the GPUs. From the specs it says that 4 x PCIe 3.0 x16 (x16, x16/x16, x16/x8/x16, x16/x8/x16/x8) are supported. However, I found an infographic that apparently shows 3 x16 and one x8 GPU support.  The slots should be far enough apart to fit all the big GPUs. The motherboard can also be extended to 128GB which will last for quite some time. Hardware Raid 1 support is also a nice bonus.
 
GPUs
Dual RTX 2080Ti is more than enough to get started. Thermal throttling is a big concern in multi-GPU builds so either I use blower cards or water cooled cards. The free slots can holds two more cards, either 2080Tis, or maybe even an RTX Titan at some point if I want the sweet VRAM.
 
PSU
While 1200W is too much for this build, if I extend it with up to two GPUs I will greatly appreciate this power. I also chose a multirail PSU.
 
Storage & RAM
An M.2 drive for the working data and two HDDs for cold storage that will be put into RAID 1. Maybe even with ZFS file system. (any opinions on ZFS?). 64GB ram is currently plenty. 3200 CAS 16 is apparently a sweet spot for RAM so I chose what seemed a good deal.
 
Cooling
A very important part is cooling. I plan an aio watercooler for the CPU and blower style GPUs. Blower GPUs rather than hybrid cooled GPUs because they are a bit cheaper and I might want to build a custom loop in the future to reduce the noise and cool slightly better.
 
Case
I think that the mid tower case is a bit tight for all the stuff but it should still work. This might be a pain point when I want to upgrade or do a custom water loop.
 
The plan is to start with the above build and then add GPUs as the need arises for the local machine to be more powerful. After thermal issues or noise complaints from the neighbours I'll look into custom water cooling. Any comments or suggestions?
 
This is my first build