Linux Mint Forums

Is the Nvidia driver really installed ?

Most likely, but it seems not to be active
This is a case when you may have to do some editing
Check the file /etc/X11/xorg.conf
In there you should have a section something like this

Section "Device"
Identifier "Configured Video Device"
Driver "nvidia"
EndSection

If it does not say nvidia you have to change
In a terminal Change to nvidia
If you already had nvidia there or this does not help run (in a terminal)
and post the result (right click to copy)