vlc-playing DVD won't display on external monitor

[Robert P. J. Day]

Quoting Michael Hennebry <hennebry at web.cs.ndsu.nodak.edu>:

> On Thu, 23 Oct 2008, Robert P. J. Day wrote:
>
>> Quoting "Robert P. J. Day" <rpjday at crashcourse.ca>:
>>
>>> ok, as a followup to my previous post, i slapped f9 on
>>> my inspiron, then VLC and associated RPMs, popped in a DVD,
>>> it plays nicely on the laptop.
>>>
>>> then, connected an external (samsung WUXGA) flat-panel
>>> monitor via DVI, and the entire laptop display is reflected
>>> nicely on the monitor *except* for the actual DVD image in
>>> the VLC window -- that just shows up as blank, either in
>>> regular or fullscreen mode (in fullscreen mode, the entire
>>> external display is blank, even while the movie is playing
>>> on the laptop).
>>>
>>> i'm no expert at video so, somehow, the DVD image is
>>> not being passed out on DVI, while everything else is.
>>> thoughts?  is there a VLC setting to tweak this?  this is
>>> a dell inspiron 9200 so it's a fairly old system -- at
>>> least a couple years.  but until now, running external
>>> displays off that DVI port has worked just fine.  so
>>> why is the DVD video content being treated this way?
>
> I thhink that part of the problem is that the laptop is exporting a
> framebuffer and the DVD image isn't going through that frame buffer.
> Does the laptop use hardware acceleration?

   this is a mobility radeon 9600 M10 chip, and from Xorg.0.log,
i read that there is something called "xaa" acceleration (damn,
someone just walked off with the laptop).   in any event, i think
what i want is a utility to deactivate "LVDS" while leaving "DVI-0"
active, based on what i read from the X server log file.

   aticonfig?  something like that, i think.

rday