Как изменить разрешение экрана из командной строки?

xrandr --output DVI-I-1 --mode 640x480_75.00

xrandr: cannot find mode 640x480_75.00

Screen 0: minimum 8 x 8, current 1600 x 900, maximum 16384 x 16384
DVI-I-0 disconnected primary (normal left inverted right x axis y axis)
DVI-I-1 connected 1600x900+0+0 (normal left inverted right x axis y axis) 443mm x 249mm
   1600x900      60.00*+
   1440x900      74.98    59.89  
   1280x800      59.81  
   1280x720      60.00    50.00  
   1152x864      75.00  
   1024x768      75.03    70.07    60.00  
   800x600       75.00    72.19    60.32    56.25  
   720x576       50.00  
   720x480       59.94  
   640x480       75.00    72.81    59.94