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  1. #1

    Angry [Ubuntu 10.04] Force Screen Resolution / xrandr not working!


    I need a way to force my screen resolution on Ubuntu 10.04 to above 800x600 pixels. The screen connected to it runs on 1920x1080 by default and everything was working until yesterday.

    EDIT: Please read the last lines of this post! It may be the quickest solution!

    To overcome a KVM switch problem with Windows 7, I had to remove pin 12 from my VGA cable connected to the screen. Now the issue with Windows 7 is fixed, and in the beginning Ubuntu didn't mind, either, until I restarted the computer.

    Now the only resolutions available are 640x480 and 800x600, which are not really useful for working with the computer.

    I tried the xrandr approach found on many websites to force the resolution, but when applying it just tells me that "resolutions above 800x600 are not supported" and does nothing.

    Is there a way to REALLY force the resolution? And if you guys know one, I would love to find another one for Windows, as well...


    If you want to know the whole problem:
    Computer 1, running Windows 7, connected to Screen 1 and 2 (both 1920x1080).
    Computer 2, running Windows 7 + Ubuntu 10.04, ALSO connected to screen 2 using KVM switch.

    First issue:
    When switching from Com 1 to Com 2, Screen 2 is really disconnected from it and my extended dual screen layout will be reset, moving all my windows to screen 1, which sucks. When switching back to Com 1, the extended layout is NOT restored, and my primary screen will be Screen 2 (I have no clue why). Screen 1 stays black. Manually reconfiguring the screens helps out, but that's no good solution when switching quite often.

    SOLUTION to issue 1:
    Removing pin 12 from the VGA cable to screen 2. Now Com 1 doesn't recognize that Screen 2 is disconnected and keeps everything the way it's supposed to be. After the first restart, the screen resolution on Com 1 Screen 2 was messed up as well and could not be set to 1920x1080 in Windows, but luckily the nvidia drivers allowed me to force it. Working perfectly.
    Since I didn't restart Com 2 after removing the pin, Ubuntu was still running nicely on 1920x1080.

    Second issue:
    After a restart, both Windows and Linux on Com 2 can't recognize the screen any more and thus don't want to allow me to set the resolution. On Windows it's not that bad, I can at least set the resolution to 1600x1200, which messes up the format but at least I can see more than a few lines on my screen! Using different tools to force it to 1920x1080 didn't work, and since there is an S3 graphics card in the machine, the nvidia driver approach didn't work out.
    Ubuntu gives me only the resolutions mentioned above, and also ignores any trials using xrandr. With 800x600 I can barely open my files and edit them!
    Possible solutions (as least whay I can think of):
    1. Find a way to force the resolution, at least on linux. 1600x1200 on Windows isn't that bad.
    2. Find a better workaround for my KVM problem, not removing pin 12 (I have some spare, untouched VGA cables)

    Maybe I found a fix for the problem on Ubuntu, but I can't get it to work. It seems I can fake my EDID information using the trick:
    I got the raw file, but my Ubuntu 10.04 doesn't seem to have the xorg.conf file. I created it at /usr/lib/X11/xorg.conf.d/ according to the web, and copied all the stuff outputted by "sudo Xorg -configure" in it, then added the line mentioned in the link above, but nothing happens.
    Last edited by multimolti; 11-21-2011 at 05:43 PM.

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