Ubuntu 12.04 – The System is running in low-graphics mode

How do we fix it?

There is simple fix for this issue. Once you get the error on your screen press ALT+CTRL+F1, once in new screen type/run these commands

sudo apt-get update
sudo apt-get purge flglrx
sudo reboot

The message should be gone, if not there is good chnage that you have also trouble with gdm and you can fix it in these steps:

Again press ALT+CTRL+F1 and run these commands

sudo apt-get install gdm
sudo service gdm restart