Have you tried the *vga=###* where ### is one of the valid VGA values,
using this on the GRUB linux kernel line?  This has worked for me on some
recent kernels/x-servers where xrandr can't force the screen resolution.  I
have used this with *nouveau.noaccel=1* and sometimes *acpi=off* in problem
situations to force the resolution where hardware acceleration enabled just
causes the graphics processor to freeze, causing a reboot necessary.  This
does NOT work on GNOME, KDE, Unity, Cinnamon, etc., but does work for Mate
and Xfce without Compiz enabled.

Hope this helps.

Carl Snyder

On Thu, Sep 3, 2015 at 4:45 PM, BJB <email address hidden> wrote:

> Trying to solve #874694 (only getting 640x480 maximum resolution instead
> of 1024x768), I see also an Amilo L6820 with Intel 82845G/GL/GE Chipset.
> This blocks my attempts to force the screen resolution at xrandr level.
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1078695
>
> Title:
>   xrandr : Failed to get size of gamma for output default
>
> Status in x11-utils package in Ubuntu:
>   Confirmed
>
> Bug description:
>   I have been tracking in the Ubuntu & Linux Mint forums when people have
> problems with the resolution of their screens not being able to be set to
> the native resolution of their displays.  Normally, that can be fixed by
> either xrandr or xorg.conf settings, but occasionally when xrandr is typed
> on a line by itself to check the configuration of the X display, the return
> is [code]$ xrandr
>   xrandr : failed to get size of gamma for output default
>   Screen 0: blah blah
>   default :  more blah blah[/code]When this has occurred, the output
> maximum resolution can NOT be changed, and I haven't found any way to fix
> the problem.
>
>   [background] My particular rig is a custom built with a BIOStar N68S3B
>   motherboard, AMD Athlon II x3 processor, 8G RAM, nVidia GeForce 7025
>   display adapter on the motherboard, Etronix 1701B display.  I have
>   fought getting my maximum resolution (1280x1024) on this monitor since
>   7.10 Gutsy Gibbon, and used a custom xorg.conf file until it stopped
>   working, around 9.10, and have used xrandr since.  (I stopped using
>   Ubuntu as my primary OS of choice when Unity came out, because my rig
>   did not support Compiz or graphics acceleration.  Xubuntu, Linux Mint
>   Debian Edition, or Debian are my primaries now.) The EDID on this
>   monitor is not read correctly/has never been read correctly, and I
>   have always been stuck with the default resolution on Live media,
>   except occasionally on Puppy or Elive, through two different main
>   machines.  My first Linux install was on an eMachines T5212 with an
>   nVidia GeForce 6200 128M graphics memory, 2G RAM.[/Background]
>
>   I noticed that on a Bodhi 2.0 Live media that the xrandr did not work
>   because x11-xserver-utils package was not installed.  I was checking
>   out the Live media, because my Bodhi 2.0 virtual machine exhibits the
>   same problems reported by laptop users, that is, the Failed to get
>   size of gamma for output default and unable to use xrandr to add a
>   higher resolution display.  When I added the x11-xserver-utils package
>   to the Live running install, I could use xrandr to properly get the
>   size of gamma and reset the display to 1280x1024.  I re-installed from
>   the SAME live media to my Bodhi VirtualBox VM, still the same graphics
>   problem.  x11-xserver-utils was installed during updates, but xrandr
>   still returned no gamma, display as 'default', and no ability to set
>   resolution higher than 1024x768 detected at install.
>
>   I still have about 2 weeks laid-off from my primary work, so if there
>   is anything further I can do to help, just let me know.
>
> To manage notifications about this bug go to:
>
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>