GPU passthrough to Windows 10 - half working

I am trying to get a GPU to work on Windows 10. Windows can see it, but it can't use it. When I start Nvidia Control Panel it doesn't open at all.
Here is the HWinfo64 screenshot. As you can see the GPU is there, I just can't use it.
https://disk.yandex.com/i/80X3ToiTV1tK5w

I added the GPU with 'all functions', 'primary', 'pci-express' and different combinations of that.
https://disk.yandex.com/i/108Su4vjTKMFvw

I understand only one VM can use the GPU at a time.

I tested...

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