xrandr --current

Screen 0: minimum 320 x 200, current 3286 x 1080, maximum 32767 x 32767
LVDS1 connected 1366x768+0+0 (normal left inverted right x axis y axis) 344mm x 194mm
   1366x768       60.0*+
   1024x768       60.0
   800x600        60.3     56.2
   640x480        59.9
VGA1 disconnected (normal left inverted right x axis y axis)
HDMI1 connected primary 1920x1080+1366+0 (normal left inverted right x axis y axis) 477mm x 268mm
   1920x1080      60.0*+   50.0     59.9
   1920x1080i     60.1     50.0     60.0
   1680x1050      59.9
   1280x1024      60.0
   1280x960       60.0
   1152x864       60.0
   1280x720       60.0     50.0     59.9
   1024x768       60.0
   800x600        60.3
   720x576        50.0
   720x480        60.0     59.9
   640x480        60.0     59.9
DP1 disconnected (normal left inverted right x axis y axis)