Dual screen on ATI 9600 | NV350 AQ using radeon driver - clone only ?

[Torbjørn Thorsen - Nextline]

Alex Deucher wrote:
> On 3/16/09, Torbjørn Thorsen - Nextline <torbjorn at nextline.no> wrote:
>> I have to identical monitors running at 1280x1024.
>>
>>  torbjorn at torbjorn-desktop:~$ xrandr | grep connected
>>  VGA-0 connected 1280x1024+0+0 (normal left inverted right x axis y axis)
>>  338mm x 270mm
>>  DVI-0 connected 1280x1024+0+0 (normal left inverted right x axis y axis)
>>  338mm x 270mm
>>  S-video disconnected (normal left inverted right x axis y axis)
>>
>>  The first problem was the Virtual size was too small to fit two of both
>>  outputs, so that got configured in xorg.conf.
>>
>>  Screen 0: minimum 320 x 200, current 1280 x 1024, maximum 2560 x 1024
>>
>>  So now I should be ready for running dual screen ?
>>
>>  torbjorn at torbjorn-desktop:~$ xrandr --dryrun --output DVI-0 --right-of VGA-0
>>  screen 0: 2560x1024 675x270 mm  96.33dpi
>>  crtc 0:    1280x1024   60.0 +1280+0 "DVI-0" "VGA-0"
>>
>>  The result of doing this is that both outputs end up with the same
>>  offset, in effect, I can only see the right side of the virtual screen.
>>
>>  torbjorn at torbjorn-desktop:~$ xrandr | grep connected
>>  VGA-0 connected 1280x1024+1280+0 (normal left inverted right x axis y
>>  axis) 338mm x 270mm
>>  DVI-0 connected 1280x1024+1280+0 (normal left inverted right x axis y
>>  axis) 338mm x 270mm
>>
>>  I have tried lots of different ways to get them to show the whole
>>  virtual screen, including using --pos, but I can't get them to split.
>>  The outputs always see the same area of the virtual screen.
>>
>>  If anybody could point me in the right direction, I would be very grateful.
> 
> Both outputs are probably ending up on the same crtc by default (use
> xrandr --verbose to verify).  So you probably want something like:
> xrandr --output DVI-0 --crtc 1 --mode 1280x1024 --right-of VGA-0
> 
> This page has a lot of good information about configuration using xrandr:
> http://wiki.debian.org/XStrikeForce/HowToRandR12
> 
> Alex

Thank you very much, Alex, you were right on the money.
I had tried fiddling a bit with the crtc parameter previously, but that 
only resulted in a blank screen.

Specifying --auto sorted that out quite nicely, and I now have exactly 
the setup I wanted, thanks.
Hey, this xrandr stuff from the future is pretty cool :-)

I feel slightly embarrassed that it only took 5 minutes to fix using 
that xrandr line you provided, but alas, all's well that ends well.

-- Torbjørn