Realtime render VJ 4U rack pc - 3900x or 2950x ?

[Stroombeestje]

Hello everyone, 

I am a VJ /video artist and planning to build a new desktop inside a 4u 19inch rack pc

Processor: I am planning to use a 3900x or a Threadripper 2950X
Graphics cards: two 2070 gtx ( need to run up to 6 HD projectors) 
A capture card ideally with two hdmi inputs
10GB Ethernet connection (for streaming video 6k or 8k between other computers by NDI) 

Questions:
My preference is to use to 3900

But i am afraid this processor has not enough PCI express lanes for two GPU,s and a capture card. 
(Note it is for me not about gaming performances I need as much reachable V-ram possibly.)

Also would like to have some toughs about transportation 
I use this a reference project https://pcpartpicker.com/b/B8NQzy

greetings 

 

[Windows7ge]

Between the CPU and the Chipset the 3900X would have enough lanes for 2 GPU's, a capture card, and 10Gbit Ethernet. You should be more worried about finding a motherboard that can fit it all.

 

Personally I would go for the 2950X. This gives you access to quad-channel memory and enables you to have up to double the RAM in comparison to the AM4 platform. Of course this depends on if you think you can leverage that much RAM. If not the AM4 should be a money saver. It should still support up to 128GB of RAM and will have enough lanes for your 4 AICs.

[mariushm]

You can go with 3900

 

Go with an old x470 motherboard, which splits the x16 slot from CPU into 2 x8 slots, and has a third x16 slot that's electrically x4 from chipset ... use that for your capture card (4 pci-e 2.0 or 3.0 from chipset 2-4 GB/s).

 

That leaves you with one or several pci-e x1 slots which you can use for your 10g network card - a pci-e 3.0 x1 slot can do 970 MB/s - yeah, most 10g network cards are pci-e x4 or x8 but they'll run on a single lane. You can either cut a notch in the pci-e connector of the card or just use a pci-e riser cable that converts a x1 slot to x16. 

 

Alternatively, you can buy an adapter which converts the M.2 lanes (x4) into an actual pci-e x4 slot.

It should work with most motherboards, it depends on BIOS. 

But note that some motherboards will disable that x4 pci-e slot when m.2 connector is used, others will disable one or to pci-e x1 slots.

 

Here's a bunch of motherboards that would work : https://www.newegg.com/p/pl?N=100007625 601292784 601311650 600474769 8000&Order=PRICE

 

This one has decent VRM and will work, but two pci-e x1 will be unusable if you use 3rd pci-e x16 slot (they share bandwidth with it) - you'll still have the working m.2 x4 and one pci-e x1 slot

ASUS Prime X470-Pro AM4 AMD X470 SATA 6Gb/s ATX AMD Motherboard

 

This one has a decent VRM and heatsink capable of handling 3900 without any worries (but if you use m.2 with nvme it disables 3rd pci-e x16 slot... you can use SATA m.2 just fine)

MSI PERFORMANCE GAMING X470 GAMING PLUS AM4 AMD X470 SATA 6Gb/s USB 3.1 HDMI ATX AMD Motherboard

You can use this document to figure out which boards can safely handle your 3900 (look for two green checkmarks in the middle columns or at least a green and a yellow