One of the big problems is with the graphics cards, because the vendors block a driver functionality ( SR-IOV ) for consumer GPUs that would allow single GPU passthrough for VMs.
The alternative is to leave the system headless (reboot needed, and the VM need to run as root), or to use two graphics cards (wasting power, hardware resources, etc.), for which you also need to add an extra delay layer inside the VM for to re-send the graphics back to the screen, or to connect two wire inputs to the monitor.
One of the big problems is with the graphics cards, because the vendors block a driver functionality ( SR-IOV ) for consumer GPUs that would allow single GPU passthrough for VMs.
The alternative is to leave the system headless (reboot needed, and the VM need to run as root), or to use two graphics cards (wasting power, hardware resources, etc.), for which you also need to add an extra delay layer inside the VM for to re-send the graphics back to the screen, or to connect two wire inputs to the monitor.