Setting resolution of external monitor

[Oliver Block]

Dear Eric,

thank you for your answer.

On Thu, May 21, 2009 at 12:43:54PM +0200, Éric Piel wrote:
[...]
> If the laptop's panel doesn't have to move, it's possible to do this
> just with xrandr 1.2.
Yes, this would be totally fine.

> As the 1920x1080 modeline seems to be detected and accepted by the
> driver, it's a bit weird why it doesn't appears in xrandr. Maybe should
> you try with a more recent xserver/radeonhd?
I am using a freshly installed Debian lenny. Since I have no experience
in compiling xserver / drivers, I would like to stay with the Debian
packages. Or is there any clean way to try another xserver in Debian? Is
there maybe a simple way to build .deb packages for newer X servers on
lenny? I know this might be a little bit OT.

> Otherwise, have you tried forcing the mode of the VGA_1 output?
> Something like:
> xrandr --newmode "1920x1080n"  148.50  1920 2008 2052 2200  1080 1084
> 1089 1125 +hsync +vsync
> xrandr --addmode VGA_1 "1920x1080n"
> xrandr --output VGA_1 --mode "1920x1080n"
I tried this. This first command (newmode) works, but the second fails.

$ xrandr --addmode VGA_1 "1920x1080n"
X Error of failed request:  BadMatch (invalid parameter attributes)
  Major opcode of failed request:  155 (RANDR)
  Minor opcode of failed request:  18 ()
  Serial number of failed request:  17
  Current serial number in output stream:  18

Oliver