xrandr

$ xrandr
Screen 0: minimum 8 x 8, current 5120 x 1440, maximum 16384 x 16384
DVI-I-0 disconnected (normal left inverted right x axis y axis)
DP-0.8 connected primary 2560x1440+0+0 (normal left inverted right x axis y axis) 553mm x 311mm
   2560x1440     59.95*+
   2048x1152     60.00
   1920x1200     59.88
   1920x1080     60.00    59.94    50.00    29.97    25.00    23.97    60.05    60.00    50.04
   1680x1050     59.95
   1600x1200     60.00
   1280x1024     75.02    60.02
   1280x720      60.00    59.94    50.00
   1200x960      59.90
   1152x864      75.00
   1024x768      75.03    60.00
   800x600       75.00    60.32
   720x576       50.00    50.08
   720x480       59.94    60.05
   640x480       75.00    59.94    59.93
DP-0.1.8 connected 2560x1440+2560+0 (normal left inverted right x axis y axis) 553mm x 311mm
   2560x1440     59.95*+
   2048x1152     60.00
   1920x1200     59.88
   1920x1080     60.00    59.94    50.00    29.97    25.00    23.97    60.05    60.00    50.04
   1680x1050     59.95
   1600x1200     60.00
   1280x1024     75.02    60.02
   1280x720      60.00    59.94    50.00
   1200x960      59.90
   1152x864      75.00
   1024x768      75.03    60.00
   800x600       75.00    60.32
   720x576       50.00    50.08
   720x480       59.94    60.05
   640x480       75.00    59.94    59.93
DVI-I-1 disconnected (normal left inverted right x axis y axis)
HDMI-0 disconnected (normal left inverted right x axis y axis)
DP-0 disconnected (normal left inverted right x axis y axis)
DP-1 disconnected (normal left inverted right x axis y axis)
DVI-D-0 disconnected (normal left inverted right x axis y axis)