Bug 2935

Summary:	OpenGL applications with Radeon MergedFB causes one monitor to blank
Product:	DRI	Reporter:	Aaron VanDevender <sig>
Component:	General	Assignee:	Default DRI bug account <dri-devel>
Status:	RESOLVED DUPLICATE	QA Contact:
Severity:	normal
Priority:	high
Version:	unspecified
Hardware:	x86 (IA32)
OS:	Linux (All)
Whiteboard:
i915 platform:		i915 features:

Description Aaron VanDevender 2005-04-08 10:20:26 UTC

I have a Radeon 9200SE running with two monitors in MergedFB mode. Monitor0 is a
DVI @1600x1200 and Monitor1 is VGA @1024x768. Everything works fine, glxinfo
reports that direct rendering is on, until I run a GL application such as
glxgears. When that happens Monitor 0 goes blank. Monitor1 stays on. It doesn't
matter which monitor the glxgears window appears in, Monitor 0 always goes
blank.   When I close glxgears, monitor0 comes back. Its not that the monitor
goes into powersaving mode, since the monitor powerlight stays green and not
amber. It just goes black. I am using xorg 6.8.2. While glxgears is running it
gets good framerates (624 FPS) so the dri is somewhat working.

Comment 1 Alex Deucher 2005-04-08 12:16:48 UTC

This is a known problem with SE cards.  I believe there is a bandwidth
limitation when running the DVI port at high resolutions.  try messing with the
displaypriority option (see the radeon man page) and you may also want to try
running your panel at 50 or 55Hz rather than 60Hz or whatever it's currently at.

Comment 2 Erik Andren 2006-05-10 06:49:40 UTC

Did Alex suggestions help?

Comment 3 Alex Deucher 2006-05-10 07:16:23 UTC

you might also want to try the xorg from cvs as the handling of the tmds has
been improved.  Also, using modes with reduced blanking intervals help.

Comment 4 Aaron VanDevender 2006-05-10 08:11:26 UTC

I'm having trouble convincing X that it should run at 55 Hz. I've tried things like:

VertRefresh 55.0

And 

Option "DDCMode" "no"

but it still insists on driving the monitor at 60 Hz, even though this should be
an out of range mode, according to the VertRefresh. If you have any suggestions
on how to get X to run at a different refresh rate, I'll be happy to try it.

Comment 5 Alex Deucher 2006-05-10 08:40:26 UTC

(In reply to comment #4)
> I'm having trouble convincing X that it should run at 55 Hz. I've tried things
like:
> 
> VertRefresh 55.0
> 
> And 
> 
> Option "DDCMode" "no"
> 
> but it still insists on driving the monitor at 60 Hz, even though this should be
> an out of range mode, according to the VertRefresh. If you have any suggestions
> on how to get X to run at a different refresh rate, I'll be happy to try it.


Currently, digital outputs do not accept user defined modelines on radeon.

Comment 6 Aaron VanDevender 2006-05-10 08:49:35 UTC

(In reply to comment #5)
> Currently, digital outputs do not accept user defined modelines on radeon.

So does that mean it is impossible to try your suggestion from comment #1 ?

Comment 7 Alex Deucher 2006-05-10 09:06:17 UTC

(In reply to comment #6)
> (In reply to comment #5)
> > Currently, digital outputs do not accept user defined modelines on radeon.
> 
> So does that mean it is impossible to try your suggestion from comment #1 ?
> 

not with out the patch from #2859

*** This bug has been marked as a duplicate of 2859 ***

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