Ubuntu screen resolution fix for some screens

I was installing Ubuntu for my cousin, on an Acer X139HQ screen, it was ok until using the proprietary nvidia drivers for accelerated 3D stuff. The fix was here: http://ubuntuforums.org/showthread.php?t=1045106&highlight=Acer+X193HQ

After installing nvidia drivers, the xorg.conf would exist then edit just as in the first post of above thread, restart, done.