Monitor on second video card doesn't display anything after login

[Richard Eames]

I have a third monitor attached to a second video card, the monitor fails to display anything after logging in. To get it to work display anything I have to disable it, then re-enable it. Not sure if this is a gnome-shell issue or clutter/mutter.

Both my cards are Radeon HD 4850, using the free drivers.

ProblemType: Bug
DistroRelease: Ubuntu 13.04
Package: gnome-shell 3.6.3.1-0ubuntu6
ProcVersionSignature: Ubuntu 3.8.0-20.31-generic 3.8.11
Uname: Linux 3.8.0-20-generic x86_64
ApportVersion: 2.9.2-0ubuntu8
Architecture: amd64
Date: Wed May 8 15:58:15 2013
DisplayManager: lightdm
EcryptfsInUse: Yes
GsettingsChanges:
 b'org.gnome.desktop.interface' b'clock-format' b"'12h'"
 b'org.gnome.desktop.interface' b'clock-show-date' b'true'
 b'org.gnome.desktop.interface' b'clock-show-seconds' b'true'
 b'org.gnome.desktop.interface' b'ubuntu-overlay-scrollbars' b'false'
InstallationDate: Installed on 2012-04-01 (401 days ago)
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012)
MarkForUpload: True
SourcePackage: gnome-shell
UpgradeStatus: Upgraded to raring on 2013-04-16 (22 days ago)

[Richard Eames (naddiseo)]

From Upstream: https://bugzilla.gnome.org/show_bug.cgi?id=700594#c4

Owen Taylor [mutter developer] 2013-05-20 16:23:46 UTC
If everything works as expected after disabling and reenabling the display in
System Settings, then this is a bug in the X server, in gnome-settings-daemon,
or (less likely) in the Mesa GL drivers.

(In the case where the display isn't working, do 'xdpyinfo| grep dimensions' -
if the monitor's pixels show up there, then it might be a Mesa bug, but if they
don't show up, then that excludes Mesa and it's either an X or g-s-d bug)

From Upstream: https://bugzilla.gnome.org/show_bug.cgi?id=700594#c5

Richard Eames [reporter] 2013-05-20 16:55:09 UTC
I sometimes have to disable/reenable the monitor multiple times before I can
get it to work. There are three cases that I get when I enable/reenable the
monitor:
1 : Works as expected, I get a screen that spans all three monitors
2 : The screen is shifted by about half the width of the third monitor
3 : Similar to 3, except that the middle monitor displays corrupt graphics.

This is what I get on case 1, and before I've done the disable/reenable.
$ xdpyinfo |grep dimen
  dimensions: 5520x1080 pixels (1461x286 millimeters)

I also tested in Ubuntu Unity with the same results, so that rules out
gnome-shell.

What's my next step for ruling out Mesa / X / g-s-d?

[Richard Eames (naddiseo)]

Attached is the output of xrandr, which is identical when it's working, and when the third monitor is black.

And xdplinfo is also the same in both conditions:
$ xdpyinfo |grep dime
  dimensions: 5520x1080 pixels (1461x286 millimeters)

[Richard Eames (naddiseo)]

Adding X to this as suggested on upstream since it's marked as NOTGNOME.

[Richard Eames (naddiseo)]

Also added Mesa and g-s-d as per upstream suggestion. I guess the unaffected packages can be marked as invalid as they are diagnosed