how to force my laptop external video refresh rate to 50 Hz?

["Robert P. J. Day" <rpjday crashcourse ca>]

  for the sake of testing an external video device, i'd like to force
the video refresh rate on my aging WUXGA dell inspiron 9200 to 50 Hz.
i can see from the xorg.conf man page that the Monitor section has a
VertRefresh option, but my current xorg.conf has no Monitor section
whatever -- i'm assuming X is then just faking up a default one.

  is there a quick way to force a lower refresh rate?  specifically,
on the DVI port.  thanks.

rday
--

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Robert P. J. Day
Linux Consulting, Training and Annoying Kernel Pedantry:
    Have classroom, will lecture.

http://crashcourse.ca                          Waterloo, Ontario, CANADA
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