To query attached displays and detect available modes

  • With the X server running, enter the following command in a terminal window:
xrandr

Output is similar to the following:

Screen 0: minimum 8 x 8, current 2560 x 1600, maximum 16384 x 16384
DP-0 connected primary 2560x1600+0+0 (normal left inverted right x axis y axis) 220mm x 140mm
  2560x1600     60.0*+
HDMI-0 disconnected (normal left inverted right x axis y axis)