Odd XCP-NG GPU Passthrough Behavior - GTX 1080 is running low Memory Clock, and full Core clock in Windows 10 VM

Operating Systems & Open Source Virtualization
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Greetings!

I have passed through a GTX 1080 to a Windows 10 VM. When running MSI Afterburner, and running Unigine Heaven, the GPU is reporting a full GPU Clock (2100 MHz) and a very low Memory Clock (450 MHz). This is resulting in a very low benchmark results (12-15 FPS in Unigine Heaven - default settings).

A Windows Bare Metal install would result in around 100+ FPS. I’m wondering if there is some GPU BIOS shenanigans in the passthrough (from my experience passing through the same GPU with Proxmox), or possibly from another place?

I have passed through the GPU with the steps in the XCP-NG Guide. Any one have any ideas about what could be going on?

Your friendly GPU Passthrough Detective.
Thank you!

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I hope experts help you!

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I hope experts also help; unfortunately, I am not one in this particular area. So now, I am your man if you have a network issue. @YouSirName, I do have a couple of ideas of what is going on, the graphics card isn’t passing through properly, or Nividia cards are not entirely supported yet on XCP-NG. Unfortunately, @YouSirName doesn’t give very much information, so the only thing someone could suggest is to change hypervisors or pin some of his CPU threads to the virtual machine.

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Update:

I’ve moved the graphics card to a bare metal Linux machine, where the memory clock was also stuck at 450 mHz.

Reflashing the vBios solved the issue on the bare metal machine.