Well this put me on the right track. I have a Unraid server with a single GPU a MSI Geforce GT 710.
I was having trouble with a simular issue aswell. I tried to install a Ubuntu VM. The installation would go through, but after the installation it simply looked like it didn't work anymore. Black screen all the way. I tried every suggestion I could find.
Turns out... the installation was simply installing the wrong nvidia drivers...
Setting up the VM with my GPU passed through worked, after the install black screen. I changed my Graphics card in the VM to VNC. Logged in and installed the correct drivers using the following commands:
sudo apt-get purge nvidia*
sudo add-apt-repository ppa:graphics-drivers
sudo apt-get update
sudo apt-get install nvidia-470
Afterwards I shutdown the VM, changed the graphics card setting back to my GT 710 and voila everything works as a charm again.
This took me way to long to figure out...