upgrade from debian etch to debian testing (lenny) results in garbled screen

[Hartmut Niemann]

Am Dienstag 30 Dezember 2008 schrieb Alex Deucher:
> On Sun, Dec 28, 2008 at 2:31 PM, Hartmut Niemann <Hartmut.Niemann at gmx.de> wrote:
> > Hello everybody!
> > I upgraded the following system from debian etch to current testing:
> >
> > AMD Athlon(tm) XP 2600+
> > VIA KT400 chipset
> > ATI Technologies Inc RV280 [Radeon 9200 SE] (rev 01) (according to lspci)
> > BENQ G2400W (1920x1200)
> >
> > and the xorg.conf that worked fine with debian etch results in a totally distorted screen,
> > with diagonal stripes that have about the color the screen should have
> > (light blue for the login screen, and the main colors of the background picture
> > after a more or less blind login seemed right) Like the rendering engine
> > has a different opinion how many pixels are in a line from the output stage.
> >
> > Versions of debian packages:
> > xserver-xorg-video-ati    1:6.9.0-1+
> >
> 
> Do you have the same monitor plugged into both the DVI and VGA ports
> on your card?  If so, remove one or the other as the monitor may be
> getting confused.  Also comment out or remove the monitor section in
> your config because it maybe overriding the 1920x1200 mode from your
> monitor's EDID with your modeline.  I suspect your monitor doesn't
> like the 193 Mhz pixel clock in your modeline.  the preferred clock
> from your monitor's EDID is 154 Mhz.

Hello Alex,
thank you for your reply and the hints you gave.
I commented the monitor section out and checked that the VGA cable is removed,
which gave me the same distorted picture I described above

http://www.nieleute.de/Xorg.0.log.agpmode

The monitor reported correctly 1920x1200 at 60Hz and, as before, I had a sharp and
correctly moving cursor.

And then I remembered a hint you gave me about a year ago, and that helped:
>If it's an AGP card, try forcing it
>into PCI mode (Option "BusType" "PCI").
This gives me a working 1920x1200 at 60Hz. Yeah!
http://www.nieleute.de/Xorg.0.log.pcimode
http://www.nieleute.de/xorg.conf.pcimode

Is this a broken mainboard - graphics combination?

I am happy that it works again, but if you are interested in 
hunting that bug and resolving that problem, I'd like to help 
in every way I can.

Happy New Year to all!

Hartmut Niemann