I have a dell M4600 with NVidia Quattro K2000m. After first installing Ubuntu it showed 2 experimental drives in "Additional drivers". After reboot, they were gone. And I don't have any xorg.conf. It doesn't exist. And Ubuntu can't recognize the graphics card. It says "unknown".
External monitor works through VGA, but not HDMI or display-port.
Any ideas on what's wrong and what to do?