(on ubuntu 18.04 beta 2)i had the same problem after upgrading to nvidia-drivers-390.48, than i could not login even using nouveau after removing all nvidia driver.
GDM3 could not manage to boot properly but just installing lightdm and setting it to default let me login successfully (i did not remove gdm so it was not necessary to do so to fix it) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1752053 Title: nvidia-390 fails to boot graphical display To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/mesa/+bug/1752053/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs