Black screen when using sys-gui-gpu

Yesterday I started playing around with sys-gui-gpu but whatever I do it will still end in the same black screen situation.
Here are a few things I done:

  • Manually reattaching the GPU. I did it because the it didn’t start initaly(crashed during boot).
  • Hiding the GPU from dom0
  • Trying everything again by modifying the salt to use f37 instead of f36.

I also was not able to find anything that might tell me if lightdm crashes or not in the guest logs. Trying to start sys-gui-gpu without the gpu attached so I can try to open an terminal in it also failed(it will take control over the keyboard).

Any idea on what should I try?