Display resolution sometimes wrong on power up

Colin Law clanlaw at googlemail.com
Tue Jun 30 07:21:34 UTC 2009

2009/6/28 NoOp <glgxg at sbcglobal.net>:
> On 06/28/2009 04:14 AM, Colin Law wrote:
>> I have a strange situation with one of my machines. Running Jaunty
>> Desktop (new installation). Sometimes on power up the display goes to
>> 800x600 instead of 1024x768.  If I then run xrandr it shows only
>> 800x600 and 640x480.  If I logout and in again then it goes to
>> 1024x768 and xrandr shows the full set of valid settings.  I have
>> Visual Effects off.
> Does it make a difference if the display is off/on when you boot? Try it
> both ways (hard boot's not just restart) to test. If it only occurs when
> the display is turned off during boot then you may have to modify add
> the display specs to your xorg.conf file. What is the specific brand &
> model of the display?

Rather non-intuitively I have not managed to make it fail if the
monitor is powered off.  It seems to fail about once in five times if
the monitor is on.  It is possible that it does fail when monitor off
but I have just not managed to hit it.

It is a Dell M782p monitor.  I am guessing that for some reason the
monitor is not being correctly identified on start up.  I suppose the
identification circuitry must be powered by from the PC otherwise it
would never work if the monitor was off.  Is the detection logged
somewhere?  I had a look but could not find anything, but I was likely
looking in the wrong log.


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