I made a fresh install of Fedora 28 (kernel 4.17) on my Thinkpad P50 with NVidia Quadro M1000M. I have had trouble with external screen (did not work) so I decided to install proprietary NVidia drivers.
In the end I ended up with working environment once I set BIOS to use discrete graphics only (not hybrid), but after ~2 hours the system got stuck (when I tried to install xrandr to adjust brightness) and I hard-rebooted. Since then I can't login into Gnome; both screens turn black and I can only see the cursor. I have successfully installed Cinnamon and that works. However since I am more used to Gnome I'd prefer to be able to use it.
Reinstalling (dnf remove gdm && dnf install gdm) did not help. I have disabled Wayland in /etc/gdm/custom.conf but to no avail - I somehow even lost the 'Gnome Classic' option in the login screen.
I've tried to get back to Nouveau but I am stuck on laptop-screen only on 1024x768 - and the driver is not black-listed in any file in /etc/modprobe.d/. I have tried both 390 and 396 drivers (compiled myself) and 396 from negativo17, same result.
What configuration could get broken?