Fix - GPU Passthrough not working when using NVMe passthrough

[marhycz]

Hi guys,

I just wanted to share my findings if it helps anyone encoutering same hiccup.

 

I wanted to set up a VM for gaming with GPU Passthrough (In my case AMD RX 6900 XT), I enabled the SR-IOV and IOMMU in bios, set up the VM and also passed through NVME SSD drive that will be my game library.

 

However even though Unraid did not show any errors when starting the VM, I just could not see the GPU output, it wasn't even detected in Windows device manager.

 

I then proceeed to try passthrough the GPU to my Fedora VM and that worked immediately. I looked for differences in configuration and I found out that even when you are using PCIe passthrough for SSD you also need to create at least one virtual hard drive. You do not have to use it, you do not have to format it.

 

Just in the VM edit settings, create empty qcow2 virtio drive with any size. The VM will then successfully output video via passed through GPU.

 

My specs:

Asrock B650M PG Riptide

AMD 7700 Ryzen

6900 XT GPU

and NVMe SSD that I used for passthrough was Kingston KC2000.

 

BIOS Settings:

- SR-IOV Enabled

- Above 4G Decoding enabled

- Resizable Bar (Rebar) Enabled (also works with disabled)
VM Settings:

OVMF / Q35

 

I didnt have to pass any VBIOS file.