Intel 915GM dual screen (1280x1024 and 1024x768)

[Peter Langfelder]

On Thu, Nov 6, 2008 at 5:47 AM, Valent Turkovic
<valent.turkovic at gmail.com> wrote:
> Hi,
> I'm running Fedora 9 and Fedora 10 Linux (prerelase) on IBM R52 laptop
> with Intel 915GM video chip.
>
> I'm now using only one monitor - external 19" Samsung, but I would
> like if possible to also use laptop's screen.
>
> Is it possible to setup dual screen with external moninitor as main
> monitor with resolution of 1280x1024 and laptop's monitor as secundary
> monitor (1024x768).
> I have been trying this using xrandr and also with configuring
> xorg.conf but with no success :(
>
> If got the logic right I need one virtual screen with size of
> 2304x1024 (1280+1024). Laptop would be left to the main 19" external
> monitor so I need to have main monitor use offset of 1024 pixels. Have
> I made some wrong conclusions?
>
> One thing is really puzzling me - and that is maximal virtual screen I
> see from xrandr output:
>
> Screen 0: minimum 320x200, current 1280x1024, maximum 2048x1024
>
>
> So is it even possible to do dual screen with these resolutions on
> Intel 915GM? Why? How?

Valent,

according to what I read, e.g., here
http://www.thinkwiki.org/wiki/Xorg_RandR_1.2#Notes_from_xserver-xorg-video-intel.readme,
the Intel GM cards before 965 only have 11 bit addresses for pixels
and hence can only do 2048 pixels in either direction. Intel simply
made a stupid design decision.

Peter