Radeon Driver Default Display Resolution

Hamish hamish at travellingkiwi.com
Wed Apr 2 01:35:08 PDT 2008


On Wednesday 02 April 2008 00:00:17 you wrote:
> Hamish wrote:
> > On Tuesday 01 April 2008 13:10:49 you wrote:
> >> On Tue, Apr 1, 2008 at 4:41 AM, Hamish <hamish at travellingkiwi.com> wrote:
> >>> On Monday 31 March 2008 23:36:15 you wrote:
> >>>  > On Mon, Mar 31, 2008 at 11:07 AM, Hamish <hamish at travellingkiwi.com>
> >>>  > wrote:
> >>>
> >>>  [deleted]
> >>>
> >>>  > >  On the same vein... I find my X600 to be really really slow..
> >>>  > > Painfully slow. Could that be due to too a large desktop
> >>>  > > (2704x1050)? Or am I doing something wrong? Is an X600 just a slow
> >>>  > > card? I thought it should be good enought for compiz even... But
> >>>  > > only if you're prepared for several seconds wait whenever focus
> >>>  > > changes...
> >>>  >
> >>>  > The coordinate limits of the 3D engine are 2560x2560 and the max
> >>>  > texture size is 2048x2048.  Beyond these limits you are left with
> >>>  > basic 2D accel, which doesn't do much for modern desktops.  For now
> >>>  > you'll probably have better luck with XAA if you were using EXA.
> >>>
> >>>  That 2560x2560... Is that a hardware or software limit? If I upgraded
> >>> the card to a 3650 or 3850 would there still be these limits? (I tried
> >>> EXA for about 10 minutes... That was unusable... You could see the
> >>> window scrolling... Slower than an old XT (I mean PC-XT) with 80x25
> >>> green screen).
> >>
> >> It's a HW limit.  r6xx chips support 8k surfaces, but there's no 3D
> >> support yet.
> >>
> >>>  However I also tried a virtual desktop of 2048x1050... And got two
> >>> display of 1024 width. And the X600 was just as slow then as it was
> >>> with the 2704 virtual width. (I verified the 2048 virtual width by
> >>> attempting to resize the large monitor to 1680x1050, and got the xrandr
> >>> error that the virtual size was only 2048).
> >>
> >> When you say slow what do you mean?  compiz? something else?  I
> >> regularly use large dualhead desktops and performance is fine.
> >
> > Ah. Everything basically... Exceot maybe moving static windows (e.g.
> > xterm) around and drawing text... For example compiz you can see updating
> > the windows. Moving focus with transparency changes is a couple of
> > seconds per change.
> >
> >>>  I ran up oprofile... But gentoo strips libGL and the only info it
> >>> gives me at the moment is that any app spends all it's time somewhere
> >>> in there. Even if it's only a 1024x768 window... (I take it the 3D
> >>> engine is disabled completely is the screen area is over the limits,
> >>> rather than on a per-window/GLXContext basis?
> >>
> >> what sort of app are you running?  if it's libGL, presumably you are
> >> using some sort of GL desktop or application.
> >
> > Ah. It's an openGL app I wrote. It displays textures (Loaded as png's) in
> > a 4 sided cube (No top or bottom). The textures are rrd graphs...
> >
> > On an nvidia 8600GTS I get > 50fps with FSAA enabled and about 2% CPU
> > with about 1100x900 window size (Without FSAA I can get the full dual
> > display @ > 50fps and a few % CPU). With X1400 (Which should be not a lot
> > faster than the X600 according to raw stats?) and fglrx drivers I can get
> > 1680x1050 full screen at > 50fps almost 0% CPU.
> >
> > But with he X600 I get 100% CPU utilisation, somewher between 0 - 1 fps
> > (And the textures all display as a grey rectangle as well, but I'll try &
> > solve the speed first since I have an older version that the textures
> > work, but just as slow).
> >
> > I ran up sysprof. And according to it I get most of the time spent
> > between radeonWriteDepthSpan_z24_s8, radeonReadDepthSpan_z24_s8, and
> > radeonReadRGBASpan_ARGB8888. Then a little bit of time (e.g about 1/20 of
> > the total) in sample_2d_linear and a couple of other routines... But the
> > majority in those 3 top routines from libGL.
> >
> > I'll have to peruse the sources from mesa to know what those all do... 
> > AM I killing things by running at a depth of 24bits? Should I bet at 32?
> > (The config was written by X -configure because of the original config I
> > had caused a blank screen).
>
> Looks like software rasterizer fallbacks. Hard to tell without knowing
> the app - you should get a warning though on stderr the first time this
> happens.
>

Hm... I get one warning for software fallback of smoothed lines IIRC... But I 
ignored it because I only use lines in 2 places... I assumed that the 
textures would continue with hardware acceleration...
Or could it be because I request max anisotropic filtering (16 on

I tried 32bits display depth (Because I know fglrx only did 32 last time I 
tried it)... Apparently the radeon driver doesn't support 32, So fell back to 
24 only.

I can post the sourcecode of the app I suppose if anyone is really 
interested... I'll clean it up & putit somewhere.

H

> Roland





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