Hello Garry and All:

Yes, I agree: the auto-config tools are actually dangerous in some cases, and in fact we got burned already by having the Fedora "Display Manager" (aka 'system-config-display') "fix" a perfectly usable xorg.conf during this process, so I think that the OP has learned the hazards of using it - he actually said he prefers manual edits.  I have repeatedly cautioned him (and others) about this exact issue.  And I personally know that Xorg likes to pick the highest possible resolution and color depth possible - even if it results in DRI being disabled and/or a failed X-session.  And Fedora uses only the one standard file: /etc/X11/xorg.conf, no others.  I just posted another message to say that Alex's suggestions worked: DRI is enabled and working splendidly.  But thanks for your quick response and the heads-up.

Actually, I consider that hideous nvidia-settings utility to be far more dangerous than any other - it has wrecked more xorg.conf files than I care to mention.  Fortunately not an issue in this case....

Thank You again, Gentlemen, for your quick and knowledgable help on this matter.

Thanx Again and Best Regards,


"I may detest what you say, but I will defend to the death your right to say it." EB Hall, "Friends of Voltaire", 1906

----- Forwarded Message ----
From: Garry Hurley <garry.hurley.jr@gmail.com>
To: Alex Deucher <alexdeucher@gmail.com>
Cc: Vince Schiavoni <hlingler@yahoo.com>; dri-users@lists.sourceforge.net
Sent: Saturday, May 17, 2008 12:05:0-1 PM
Subject: Re: [Dri-users] ATI Radeon Mobility M6 LY w/LVDS panel and DRI

Another thing you might want to make certain of, and this is no indictment of the Red Hat product line or its customers, is that the guy you are trying to help isn't going back and using some automatic configuration editor in Fedora Core.  Most Linux distributions have one, except Slackware-based distros (for which I am extremely happy), and they tend to choose the "best" settings for your hardware.  The problem is that sometimes what the chipset supports is not what the particular card supports, i.e. some chipsets support up to a 1600x1200 resolution but the amount of memory available on the card can barely do 1084x768.  Again, this is not the fault of anyone, but once the Xorg.conf file has been manually edited, it should never be changed by running any "all-knowing" automatic tools.

Also, check to see if the xorg.conf file that he is editing is the one that his system is actually using.  Some systems duplicate the xorg.conf in multiple locations in the file system.  Editing the system file when he may have a user version would cause the same problem.  I realize you may have already checked these things, but sometimes users can be as thick as bricks.


On Fri, May 16, 2008 at 8:39 AM, Alex Deucher <alexdeucher@gmail.com> wrote:
On Fri, May 16, 2008 at 2:10 AM, Vince Schiavoni <hlingler@yahoo.com> wrote:
> Hello:
> I'm trying to help a guy on fedoraforum.org forums that has an ATI Radeon
> Mobility M6 LY chipset to get DRI working.  Here's the thread:
> http://forum.fedoraforum.org/forum/showthread.php?t=187984
> That chipset is supported by the DRI 'radeon' driver.  The Xorg.0.logs look
> good and show that everything is working great - right up until Xorg and/or
> the driver(s) try to map enough VRAM to cover the 1400x1050 LVDS panel he's
> got, at which point it all chokes because he doesn't have enough VRAM (19800
> KB required, 16000 KB available).  We've tried every xorg.conf
> option/setting that seems helpful, to reduce the display resolution to
> 1280x800 or less, but no matter what, Xorg or the drivers keep adding that
> 1400x1050 mode to the list, which inevitably leads to a failed VRAM mapping
> and DRI is disabled at that point.  Maybe we're missing something obvious,
> but I just can't figure out how to set the display resolution to a
> reasonable number that the available VRAM could handle, and not have the
> software add any more higher values to the list.  I'm hoping that someone on
> this list has experience with this kind of hardware, or has some
> advice/suggestions as to what to try to set/keep the display resolution,
> without having it be over-ridden by the drivers.  Any help will be greatly
> appreciated.

You don't have enough vram for DRI at depth 24.  try depth16:
Section "Screen"
Identifier "Screen0"
Device "Videocard0"
DefaultDepth 16
SubSection "Display"
Viewport 0 0
Depth 16

if you want to keep depth 24, you'll have to either reduce the size of
your front buffer or depth buffer.
you can use a 16 bit depth buffer by setting:
Option "DepthBits" "16"

to reduce the size of your front buffer, adjust the virtual size down:
Section "Screen"
Identifier "Screen0"
Device "Videocard0"
DefaultDepth 24
SubSection "Display"
Virtual 1024 768
Viewport 0 0
Depth 24
Modes           "1024x768" "800x600" "640x480"


This SF.net email is sponsored by: Microsoft
Defy all challenges. Microsoft(R) Visual Studio 2008.
Dri-users mailing list