I updated my Ubuntu with the normal update on December 17th, and now I have no GUI display.
It is an Lenovo 4314-9VG S/N R9-69 PE7 10/08, with 3.2.0-57-generic-pae kernel
Have tried to make sudo apt-get... install different nvidia things.
First I tried to reestablish xorg.conf with nvidia-xconfig.
Nothing has so far helped.
The first line in the xorg.conf says
version 304.108 buildmeister@swio-display-x64-rhel04-07)
To revert to a previous proprietary Nvidia driver version we will have to remove the "updates" driver from the command line.
If we can't see a terminal we can open TTY1 with Ctrl + Alt + F1. In the terminal we log in with an administrator user and password (nothing shown on typing).
Then we can purge the "updates" driver and reboot with
sudo apt-get purge nvidia-current-updates nvidia-304-updates
sudo apt-get install nvidia-current ## only if not present
sudo reboot
This should bring us the graphical desktop back.
startx.