Concept Bifurcated dual gpu

[integer]

Hi folks
I'm wanting to build a SFF pc with two GPUs. I'm planning to run Windows in a VM and a 2080ti. The 2nd card will be for Linux. I want to go Ryzen as they have 12 and 16 core available. Intel is great of course because it has integrated graphics, but not high core counts. AMD also has integrated, but only on their older and low core count 3200/3400 APUs. So that options is ruled out. Reason for high core is multiple VM's and mixed gaming and workstation workloads. Something that hopefully "does it all" would be great.

Thus one idea, was to go dual GPU (non-SLI of course) with a main 2080ti for gaming (in the Windows VM) and something small and low wattage like an AMD RX560.(or something smaller and less powerful is fine too). Heck it could even be a 25TDP part. It's just gonna run 2d only anyway. This would then take the single ITX PCIe and split it into 8x and 8x - one for the 2080TI and the other for the low TDP AMD card. Was wanting to try keep the 2nd card AMD as I might do that trick to enable VRR on RTX card via something Looking Glass. Essentially copies the frame buffer from the VM to the AMD card and you plug TV into that.

Was hoping to fit this in an M1. Any idea if my plan will work?

 

[wertigon]

You should be able to fit a 1-slot card in there with a 2 slot card. However, one of the cards will take up the PCIe slot. The case could theoretically fit a Mini-DTX board with two PCIe slots, but no such card exist for AM4.

You could do an x570 board and use one of the m.2 slots as a riser though. ASUS has a mDTX board out with four m.2 slots if that sounds reasonable.

Do be aware that a 2080 Ti would most probably be wasted unless you buy a 3900X+ and a 4k monitor since anything lower will bottleneck everything, not sure if any mITX Threadripper boards exist yet.

I am planning to do something similar but buy a 3400G for Linux and 5700 XT for VFIO/Passthrough. With that 1080p 144Hz will be great and I can upgrade to 1440p 75Hz later.

Also, this belongs in the Build forum, you will have better luck there.

 

[reasons4reasons]

If you want to do bifurcation in an M1-like volume, your best bet is the Sliger SM560, which has built-in support for a two plus one expansion slot PCIe setup in an optional configuration. If you want an AIO to cool the CPU you could also go with the Sliger SM580, though at that point you're creeping up on Ceberus volume and a mATX platform is probably signifigantly better for this use case anyway. You could maybe do this setup in an M1 with a riser and some hacking, but it'd be a little janky for my taste and it's probably better to use a case that supports it natively.

I think Asrock is the only manufacturer that supports bifurcation on their AM4 ITX boards, but I'd make sure to double and triple check the specs and the experiences of others to make sure your board supports it. With either of those Sliger cases you're going to want to use a single-slot AMD GPU, too, which for now means their workstation parts. The Radeon Pro WX 4100 their workstation RX 560 equivalent.