[RS482] Changing screen resolution garbles display

[Andreas Gustafsson]

Binary package hint: xserver-xorg-video-ati

Booting the Gutsy Tribe 5 i386 desktop CD on an MSI RS482M4
motherboard, with the VGA output of the on-board graphics
adapter connected to an iiyama ProLite E380s 1024x768 LCD display
and selecting the "Start Ubuntu in safe graphics mode" option
(because of bug #138084), the system boots successfully into
a 1024x768 desktop.

However, if I then go to Preferences / Screen resolution and select
one of the other resolutions offered, 800x600 or 640x480, the picture
disintegrates into diagonal lines reminiscent of the picture you would
get if you lose horizontal sync on a CRT.

The effect is otherwise similar to the screenshot in bug #133192, but
in my case, the mouse cursor is not shown normally but disintegrates
along with the rest of the picture.

When the screen reverts to to its original 1024x768 resolution as a
result of me not confirming the new resolution setting, the picture
is once again normal.

lspci identifies the graphics chipset as:

  01:05.0 VGA compatible controller: ATI Technologies Inc RS482 [Radeon Xpress 200]

[Andreas Gustafsson (gson)]

I said:
> (because of bug #133192)

Oops, I meant "because of bug #138084".

[Andreas Gustafsson (gson)]

I would attach a screenshot of the garbled display, but every time I try to do that,
I get a "500 Internal Server Error" from bugs.launchpad.net.

[Tormod Volden (tormodvolden)]

Can you please attach /var/log/Xorg.0.log?

[Andreas Gustafsson (gson)]

> Can you please attach /var/log/Xorg.0.log?

I would, but that, too, gives a "500 Internal Server Error", and when
I emailed the launchpad webmaster about that problem three weeks ago,
I received no reply.

Since uploading doesn't work, here's a link instead. This Xorg.0.log
is from 7.10 beta, which still exhibits the problem.

  http://www.gson.org/bugs/ubuntu/138087/Xorg.0.log

And here's a link to a screenshot of the garbled display (from tribe 5):

  http://www.gson.org/bugs/ubuntu/138087/screenshot.jpg

[Tormod Volden (tormodvolden)]

If you're the only one having problems with attaching files, it's likely a problem with your browser. Try deleting cookies and cache.

Please attach also output from xrandr --verbose.

The -tv3 package from http://ppa.launchpad.net/tormodvolden/ubuntu/pool/main/x/xserver-xorg-video-ati/ (i386 still in build queue) will have changes from current git upstream which could help.

[Andreas Gustafsson (gson)]

> If you're the only one having problems with attaching files, it's likely a problem with your browser

Even if that is the case, there is still a bug in launchpad, because errors on part of the browser
should be reported with 4xx HTTP error codes, not 5xx. Error 500 by definition means there is
a problem with the server.

> Please attach also output from xrandr --verbose.

Attached.

[Andreas Gustafsson (gson)]

> The -tv3 package from http://ppa.launchpad.net/tormodvolden/ubuntu/pool/main/x/xserver-xorg-video-ati/ (i386 still in build queue) will have changes from current git upstream which could help.

I installed xserver-xorg-video-ati_6.7.194-1ubuntu1tv3_i386.deb, restarted the X server using
alt-control-backspace, logged back in, and tried changing the resolution to 640x480.
The display was still garbled in the same way as before.

[Tormod Volden (tormodvolden)]

Sorry, I just realized you were using the vesa driver, in which case the new ati driver won't help much :)

Although this could be a bug in the vesa driver, I'll reassign it to the xorg package, since I see from the other bug that you have issues when using the ati driver as well.

[Timo Aaltonen (tjaalton)]

Probably related to your hardware. Check any BIOS updates and settings that might have something to do with it.

In any case it's not a major issue, since the native resolution works fine.

[Andreas Gustafsson (gson)]

I tried booting the Hardy Heron alpha 4 CD in safe graphics mode
(the default mode is still broken on this machine, see #188660).
Changing the resolution in Preferences / Screen resolution stil
garbles the display in the same way as before.

[Tormod Volden (tormodvolden)]

Please attach your Xorg.0.log, if possible the one from alpha 4.

[Andreas Gustafsson (gson)]

The attached Xorg.0.log is from Hardy Heron alpha 4, and was saved after making a failed attempt to change the resolution.

[Timo Aaltonen (tjaalton)]

For some reason it's using vesa for your card, although the ati driver supports it.

[Andreas Gustafsson (gson)]

> For some reason it's using vesa for your card, although the ati driver supports it.

Isn't that expected when booting in "safe graphics mode"?

[Timo Aaltonen (tjaalton)]

oh right, then the next question would be why do you do that?-)

[Andreas Gustafsson (gson)]

> oh right, then the next question would be why do you do that?-)

You wouldn't have to ask that if you had actually read the ticket.

[Andreas Gustafsson (gson)]

I tried the 8.04 release CD (ubuntu-8.04-desktop-i386.iso) and the problem is still there.

[Andreas Gustafsson (gson)]

I'd like to add that in 8.04, the screen no longer automatically reverts
to its default resolution when you don't confirm the new resolution selection
within a short timeout period. This makes the problem harder to recover
from than it previously was.

[Tormod Volden (tormodvolden)]

In 8.04 the other bug #138084 is solved, so you don't need to use "safe graphics mode", right? Do you have this problem with the default -ati driver?

[Andreas Gustafsson (gson)]

> In 8.04 the other bug #138084 is solved, so you don't need to use "safe graphics mode", right?

Bug #138084 is solved, but bug #188660 is not, so I still need to use "safe graphics mode".

[Andreas Gustafsson (gson)]

I just tried the jaunty alpha 5 i386 desktop live CD, and the bug is still there: any attempt to change the screen resolution still causes the display to be garbled as in the screenshots I attached earlier.

Also, since the display still doesn't revert to its old resolution after a timeout when you fail to confirm the new resolution in the screen resolution dialog (see bug #222297), you still have no easy way to recover when you end up with the garbled display.

Since bug #188660 is now fixed, I don't really _need_ to use safe graphics mode anymore. But it would still be nice if it worked...

[David Tombs (dgtombs)]

Same issue with a Radeon Xpress 200M. Attached is my Xorg.0.log from an attempted switch.

[David Tombs (dgtombs)]

Sorry about the bug spam. To be more specific, it is a:

01:05.0 VGA compatible controller [0300]: ATI Technologies Inc Radeon XPRESS 200M 5955 (PCIE) [1002:5955]

[Bryce Harrington (bryce)]

[This is an automatic notification.]

Hi Andreas,

This bug was reported against an earlier version of Ubuntu, can you
test if it still occurs on Lucid?

Please note we also provide technical support for older versions of
Ubuntu, but not in the bug tracker. Instead, to raise the issue through
normal support channels, please see:

    http://www.ubuntu.com/support

If you are the original reporter and can still reproduce the issue on
Lucid, please run the following command to refresh the report:

  apport-collect 138087

If you are not the original reporter, please file a new bug report, so
we can work with you as the original reporter instead (you can reference
bug 138087 in your report if you think it may be related):

  ubuntu-bug xorg

If by chance you can no longer reproduce the issue on Lucid or if you
feel it is no longer relevant, please mark the bug report 'Fix Released'
or 'Invalid' as appropriate, at the following URL:

  https://bugs.launchpad.net/ubuntu/+bug/138087

[David Tombs (dgtombs)]

OK, I opened a new bug, bug 586446, that is a likely dupe of this issue.

[Andreas Gustafsson (gson)]

> This bug was reported against an earlier version of Ubuntu, can you
> test if it still occurs on Lucid?

I'm not sure how, since Lucid does not seem to offer me the option of a "safe graphics mode" when booting the live CD.

[David Tombs (dgtombs)]

It's a bit harder to boot into VESA-only from the LiveCD now. If you can't run a virtual machine or something, I think your best bet would be to add the "nomodeset" kernel parameter at the boot menu, then play with /etc/X11/xorg.conf once booted to force the vesa driver to be used. (See my description in bug 586446 for how I reproduced it.)

[Launchpad Janitor (janitor)]

[Expired for xserver-xorg-video-vesa (Ubuntu) because there has been no activity for 60 days.]