Bug#499209: xserver-xorg-video-radeon: incorrect resolution choice for second monitor

[Brice Goglin]

Zack Weinberg wrote:
> Package: xserver-xorg-video-radeon
> Version: 1:6.9.0+git20080826.a3cc1d7a-1
> Severity: normal
>
> I have two flat-panel monitors: one has a native resolution of 1600x1200
> (on output DVI-1) the other 1920x1200 (on output DVI-0).  I wired RandR
> settings into xorg.conf that I expected to produce a 3520x1200 virtual
> desktop.  It works perfectly except for one thing: when X starts up,
> it initializes both displays to a resolution of 1600x1200 (and thus the
> virtual screen is only 3200 pixels wide).
>
> "xrandr --output DVI-0 --auto" resets the wider monitor to 1920x1200
> and after that everything is fine, but it would be nice not to have to
> run that on every login.
>
> This might be a core X server bug, but I wasn't having a problem with
> the same 1920x1200 panel as a second head on a different computer that
> uses the Intel drivers, so I'm filing it against radeon.
>   

I might be the Xserver core choosing the same resolution at startup (so
that the login screen appears in the middle of both monitors instead of
risking of having it outside one of them).

You should be able to work around the problem with PreferredMode. See
III.5 of http://wiki.debian.org/XStrikeForce/HowToRandR12

Brice