The following is default tutorial for fixing screen resolution on Ubuntu/Linux. See https://wiki.ubuntu.com/FixVideoResolutionHowto for more information.

1. Check that /etc/X11/xorg.conf contains the correct HorizSync and VertRefresh options in the “Monitor” section as follows.

sudo ddcprobe | grep monitorrange

2. The first two values returned are your HorizSync rates, the second pair is your VertRefresh values.

sudo cp /etc/X11/xorg.conf /etc/X11/xorg.conf.backup.sync_and_refresh
sudo gedit /etc/X11/xorg.conf

3. Find the following section and make sure the HorizSync and VertRefresh lines exist and have the appropriate values (e.g., 30-96 and 50-160):

Section “Monitor”
…
HorizSync 30-96
VertRefresh 50-160
EndSection

Tags | Howto, Linux, Tutorials, Ubuntu