Nothing works for me. My desktop system has a NVidia Gefore Titan X 1650 and I got a black screen after rebooting with Ubuntu 20.04 Focal.
With [CTRL]+[ALT]+[F3] I can get a login screen that is frozen with static (no flashing) cursor and non-responsive keyboard.
In safe mode from Grub the system does not boot either and displays a sequence of lines of code before it freezes.
There is no way I can do anything from a command line, so no bug report. Also I have no idea of which drivers are installed for the graphic card.
I tried to repair Ubuntu from usb drive but the test version of Ubuntu does not even recognize the already installed OS on the local drive. But it does allow me to access the drive and system files on the local disk. So is there a mean to modify the system files, extract a bug report or update the NVidia drivers in this way?