Re: Redhat 9, ATI Radeon 7500, DVI digital display -- output flaky

[Mike Godfrey <migod uwaterloo ca>]

Hi I did as you asked.

Setting the "noaccel" option did indeed make the problem go away ...
although of course now I have no acceleration.

If I removed the noaccel option and enabled either or both of the
"XaaNoOffscreenPixmaps" and "XaaNoPixmapCache" options, the problem was
there again.

Any ideas of what to try next?

-- Mike



On Wed, 2003-04-23 at 00:26, Mike A. Harris wrote:
> On Tue, 22 Apr 2003, Mike Godfrey wrote:
> 
> >Date: Tue, 22 Apr 2003 22:06:10 -0400
> >From: Mike Godfrey <migod uwaterloo ca>
> >To: xfree86-list redhat com
> >Cc: mharris redhat com
> >Content-Type: text/plain; charset=us-ascii; format=flowed
> >Subject: Re: Redhat 9, ATI Radeon 7500, DVI digital display -- output flaky
> >
> >Here is a screenshot of what I was talking about; thanks for any tips.
> >
> >
> >	http://plg.uwaterloo.ca/~migod/ftp/radeon-dvi-output.jpg
> 
> Hmm.  that looks like bad video memory corrupting offscreen 
> pixmap cache.
> 
> To test that theory, please try adding to the device section 
> of your config file: 
> 
> 	Option "noaccel"
> 
> Restart X and try to reproduce.  If the problem persists, and is 
> static and not changing, not influenced at all by moving windows 
> around, etc. then it is probably video memory corruption right in 
> the framebuffer.
> 
> If noaccel makes the problem go away, it could be offscreen video 
> memory corruption as mentioned above.  You can test this out by 
> removing option noaccel, and instead trying each of these one at 
> a time, then both together:
> 
> 	Option "XaaNoOffscreenPixmaps"
> 	Option "XaaNoPixmapCache"
> 
> Indicate if either one work, both, or neither.
> 
> It also could be some kind of Xft or RENDER wonkiness, although 
> that would be reproduceable on any hardware and shouldn't be 
> driver or card specific in that case, and would be widely 
> reported.
> 
> It's also possible to be an application specific problem although 
> from the screenshot it seems unlikely.
-- 
Michael Godfrey PhD, Assistant Professor
Nortel Networks Jr Chair, Telecommunications Software Engineering
Univ of Waterloo, School of Computer Science
email:  migod uwaterloo ca 
URL:    http://www.uwaterloo.ca/~migod