Pažiūrim kokį atnaujinimo dažnį supranta monitorius:
$ xrandr
Gaunam:
Screen 0: minimum 320 x 200, current 1280 x 1024, maximum 4096 x 4096
VGA-0 connected 1280x1024+0+0 (normal left inverted right x axis y axis) 337mm x 270mm
1280x1024 60.0*+ 75.0
1024x768 75.1 75.0 70.1 60.0
832x624 74.6
800x600 72.2 75.0 60.3 56.2
640x480 72.8 75.0 66.7 60.0
720x400 70.1
DVI-0 disconnected (normal left inverted right x axis y axis)
S-video disconnected (normal left inverted right x axis y axis)

* – dabartinis
+ – numatytasis

Keičiam į 75Hz:
$ xrandr -r 75
-r – atnaujinimo dažnis, dar gali reikėt „-s“ jei keli monitoriai