14.04 LTS unknown display, 1024x768 only

You can use xrandr:

The commands to be executed in order:

cvt 1920 1080
xrandr --newmode "1920x1080_60.00" 173.00 1920 2048 2248 2576 1080 1083 1088 1120 -hsync +vsync

The part of the line after xrandr --newmode is similar to the ouput you should get when using the cvt command, so copy the output from the "resolution_refreshRate" to the +vsync point and add it to xrandr --newmode.

Then:

xrandr --addmode LVDS1 resolution_refreshRate (don't use speechmarks)
xrandr --output LVDS1 --mode resolution_refreshRate

If you want to make the changes permanent:

• Create a bash script, xrandr.sh for example, and place your xrandr commands into it:

  #!/bin/bash
  sudo xrandr --newmode "1920x1080_60.00" 173.00 1920 2048 2248 2576 1080 1083 1088 1120 -hsync +vsync
  sudo xrandr --addmode Virtual1 1920x1080_60.00
  xrandr --output Virtual1 --mode 1920x1080_60.00

• Make the script executable with chmod +x xrandr.sh

• Search for "Startup Applications" in the dash, run it, and add the script as a startup application.

The commands will now run every time you log into your account.

Note: I'm using LVDS1 as the supposed monitor name, but yours probably won't be the same. You can find your monitor name using:

xrandr | grep " connected " | awk '{ print$1 }'

This might be useful to you.

I had the same problem with my Samsung monitor, after a lot of reasearch i found that I was using VGA cable and monitor was not detected, connecting through HDMI solved the problem and all resolutions are now listed. However, VGA all works fine with Windows.