If you try to pass through an A770 Limited Edition (or any other Arc A-Series GPU) from a Linux host to a Windows guest, you do not get any video out or detected monitors on the Arc card. But, the card is being picked up by the drivers and will run whatever workload you throw at it, just not a picture on the Monitor. The Monitor detects something on VM Boot but nothing other than a black screen is visible.
There is a "fix" found out by u/taoj17v on Reddit: "unplug all intel GPU output on host boot/VM boot. Only plug in them when VM finished boot. It worked for me. However, it hangs my kernel when guest reboots.". He also points out that it is likely a bug in the Firmware.
I thought it would be good to let you guys know the fix and draw attention to this issue to get it more likely fixed.
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