vfio: Unable to power on device, stuck in D3

Hey guys,

for the past week I've watched all the SpaceInvader One videos and tried all the different tweaks you could image to get my GPU passthrough working.

My specs are:

MOBO: Asus PRIME X370-PRO (BIOS Version 5220)

CPU: Ryzen 1700x

GPU: Asus Strix GTX 1080 Advanced (VBIOS Version 86.04.17.00.AS02)

Drives: 

• Samsung 960 EVO 250GB
• 4TB Seagate HDD
• 2TB WD HDD

I've booted in Legacy mode and tried to use the "vfio-pci.ids=10de:1b80,10de:10f0" kernel parameter to stop unraid from picking it up.

Whenever I do this, the last line of the monitor output of the graphics card is:

 vgaarb: changed VGA decodes: olddecodes=io+mem,decodes=io+mem:owns=none

 When I try to start a Win10-VM (with or without the mentioned parameter) the screen goes blank and this appears as the last line in the logfiles:

vfio: Unable to power on device, stuck in D3

I can't shutdown the VM after that and when I force stop it I get the error message:

unknown pci header type '127' for device '0000:0a:00.0'

Which of course means that the card couldn't shut down properly and a restart is required to try it again.

I've tried numerous BIOS Versions as well, but I can't install a BIOS older than version 4801 because the firmware appears to be blocked by the motherboard.

I am kinda frustrated right now because it seems like I did something wrong but I don't know what.

I sincerely hope one of you guys could help me out, that would be awesome.

Greetings