Issue with AMD GPU Passthrough on Windows 11 VM - Error 43

Hello everyone,

I'm encountering an issue while attempting to set up GPU passthrough for a Windows 11 VM on a Proxmox system, using an AMD Radeon RX 6750 XT graphics card. Below are the steps I've taken and the problems I'm running into:

  1. I used lspci to verify that the GPU is correctly grouped in IOMMU groups.
  2. I've set up VFIO bindings with the IDs of my AMD GPU (1002:73df,1002:ab28).
  3. Kernel parameters are configured with iommu=pt
    and initcall_blacklist=sysfb_init.
  4. In the QEMU config, I've set the CPU to host mode and the machine type to pc-q35-8.0 and also 7.2 and 6.2.
  5. I installed the Windows 11 OS on the VM without the passthrough GPU, then shut down the VM, added the PCI device, and set display to 'none'. I also try with Windows 10
  6. After rebooting the VM and installing the AMD drivers, I receive an error 43 in the Windows Device Manager.

Here are some additional details about my setup:

  • Proxmox version 6.5.11-7
  • AMD Radeon RX 6750 XT with the latest AMD drivers
  • Windows 11 VM with EFI and no GPU defined in the VM's configuration

Has anyone else encountered this issue or has suggestions on how to resolve it? I have followed multiple tutorials and guides, but I still can't get the passthrough to work correctly.

Thanks in advance for any help you can provide!

If needed, I can provide all my proxmox configuration, just ask !