Solution 1:
gdm may be buggy.
As a workaround, I use lightdm.
sudo dpkg-reconfigure lightdm
Choose lightdm as the display manager. And X restart works.
sudo service lightdm restart
gdm may be buggy.
As a workaround, I use lightdm.
sudo dpkg-reconfigure lightdm
Choose lightdm as the display manager. And X restart works.
sudo service lightdm restart