xrandr -q

Screen 0: minimum 320 x 200, current 2560 x 1024, maximum 2560 x 2560
DFP5 connected 1280x1024+1280+0 (normal left inverted right x axis y axis) 376mm x 301mm
   1280x1024      60.0*+
   1280x960       60.0
   1280x768       60.0
   1280x720       60.0
   1024x768       60.0
   800x600        60.3
   640x480        59.9
DFP1 disconnected (normal left inverted right x axis y axis)
DFP2 disconnected (normal left inverted right x axis y axis)
DFP3 disconnected (normal left inverted right x axis y axis)
DFP4 connected 1280x1024+0+0 (normal left inverted right x axis y axis) 376mm x 301mm
   1280x1024      60.0*+
   1280x960       60.0
   1280x768       60.0
   1280x720       60.0
   1024x768       60.0
   800x600        60.3
   640x480        59.9
CRT1 disconnected (normal left inverted right x axis y axis)