Hi,

I will try to keep it short and simple not to waste your time

I'm using Unraid primarly to create VMs for 4 users.

 

Hardware:

CPU: Threadripper 1950X (4.0 GHz) 16 cores

MOBO: MSI X399 SLI PLUS

RAM: 32GB DDR4

GPU:

Radeon RX 580 4GB

GT 710 * 3

 

The question is about GPU passthrough, is it possible to run VMs using following configuration?

1. PCIe x16 RX 580

2. PCIe x8  GT710

3. PCIe x16 GT710

4. PCIe x8  GT710

 

From what I can find there is no option to choose primary GPU i my bios

 

What works like a charm:

- only RX 580 in 3. slot (btw before displaying TianoCore logo I can see screen with glitched, primarly pink graphic and a lot of artifacts, after everything is correct)

- only GT 710 in 1. and 3. slot (VM only on GPU in 3. slot)

So on paper all GPU are compatible.

 

What does not work:

- RX 580 in 1. slot (black screen)

 

I know that nvidia GPU in 1. slot or as single GPU require dumping vbios, but how does it work with AMD GPU as primary GPU (1. slot)? The point is not to waste 1. GPU slot for Unraid GPU and if possible avoid dumping vbios of nvidia card. Do you see the possibility of passing through GPU in all 4 slots, if yes what GPU setup do you recommend? Have anyone tried setting up AMD GPU as primary GPU?

 

Thanks in advance.

Dumping vbios is recommended for all GPUs, not just Nvidia.

Nvidia is mainly to resolve error code 43. AMD is mainly to help with reset issue.

RX 580, in particular, has reset issue so you definitely should dump vbios for it.

 

The only success story I have seen so far with the RX 580 is when it's NOT being used as a primary GPU (what Unraid boots with).

So given your mobo doesn't allow picking any PCIe slot as initial display output, your only solution is to put it in a different slot instead of slot 1.

 

What's wrong with putting the RX 580 in the 3rd slot given you do have multiple GPUs?

What's preventing you from dumping vbios? It's a rather simple procedure.

1 minute ago, testdasi said:

Dumping vbios is recommended for all GPUs, not just Nvidia.

Nvidia is mainly to resolve error code 43. AMD is mainly to help with reset issue.

RX 580, in particular, has reset issue so you definitely should dump vbios for it.

 

The only success story I have seen so far with the RX 580 is when it's NOT being used as a primary GPU (what Unraid boots with).

So given your mobo doesn't allow picking any PCIe slot as initial display output, your only solution is to put it in a different slot instead of slot 1.

 

What's wrong with putting the RX 580 in the 3rd slot given you do have multiple GPUs?

What's preventing you from dumping vbios? It's a rather simple procedure.

The only thing that was preventing me is my lack of experience using Unraid. Hearing that particularly Nvidia cards require dumping vbios I thought that putting RX in 1. slot will resolve the problem, additionally there is the good practice of putting the best GPU in the first slot when it goes to building normal PCs that apparently in the server field gives more problems that benefits (given that there are even any benefits).

 

Thank you for setting me on the right track. Now I'm going to put RX in 3. slot and fill remaining slots wih GT 710.

Just one additional question, do you recommend dumbing vbios of all the cards or just the primary GPU?

With regards to the 1950X (and Threadripper in general), you might want to watch Spaceinvader One guide on lstopo and numa node.

Once you identify the NUMA nodes, these tweaks will improve gaming performance (and playability).

• Isolate cores from the numa node connected to the GPU 
• Pin cores from the GPU numa node to the appropriate VM (i.e. only the one that uses that GPU).
• Allocate RAM from the GPU numa node to the appropriate VM
• Emulator and IOThread pin (especially if you are using vdisk)
• Do not over assign cores (e.g. if you can limit to 4 cores of the same CCX, that would be best)
  • If multiple CCX is required, spread the core assignment evenly across multiple CCX (e.g. 3 + 3 is better than 3 + 4)

You should dump vbios for all the GPUs.

The procedure (if you follow SpaceInvader One guide) is very straight-forward.

Note: you have multiple GPUs so there's no excuse to download vbios from Techpowerup. One of the most annoying issues on here is downloading the wrong vbios.