As expected, Nvidia drivers have reduced my customizations. I can't login to Unity 3D session. I can't find any content to help me to uninstall the driver and I don't know what to do as I have never uninstalled them before.
For Ubuntu 12.04
Commands can be executed to terminal. You can open a terminal with Ctrl + Alt+T keys combo.
First uninstall completely the driver.
Search what packages from nvidia you have installed.
except the package
If you want to be sure that you will purge everything related to nvidia you can give this command
the asterisk in the end means (Purge everything that begins with the name nvidia-)
above command will also remove the
So after above command you should also give the installation command for
Also sometimes the nouveau driver get blacklisted from nvidia driver. With purge command it should UN-blacklisted. If you want to be sure that nouveau will be load in boot, you can force-load it by add it to /etc/modules
Last , search for the xorg.conf file and remove it as well
Although all above commands not needed, this is my way to completely purge the nvidia driver and use the open source nounveau.
To uninstall nVIDIA driver, open terminal by pressing (Ctrl+Alt+T) then type: