Public bug reported:
My Laptop HP Elitebook 8740w has two external screens connected.
1 DELL U2412M connected to vga connector
1 DELL U2415M connected to Displayport.
I worked for about a year with a single external display, just U2412M on
the displayport without the issue I decribe.
The first issue:
When booting up and with screens attatched and active, the 2415 boots in
1024x768 resolution, the 2412 boots at the same moment in 1920x1200 as it
should.
At the point where the login screen appears the 2415 goes in power save mode,
most of the time.
The 2412 displays just fine at the moment.
After logging in, turning the 2415 off and on, sometimes helps the get the
screen active (out of power save).
When it gets active, the resoltion is 1024x768, not 1920x1200.
In unity-control-center in display settings the 2415 is displayed as "Unknown
Display" and the maximum resolution I can select is 1024x768.
Second issue:
After a laptop suspend the 2415 doenst alway become active again, the 2412
always.
Turning off an on the 2415 multiple time mostly helps to get the screen active.
Current partial workaround:
xorg.conf with monitor section for 1920x1200 as in attatchment.
This doesn't solve booting in 1024x768, but solves the resolution after logging
in.
unity-control-center still lists "Unknown Screen"
Another strange behavior:
when executing xrandr command, most of the time the 2415 stays in 1024, but
after a number of executions the screen swithes to 1920x1200. At that moment
xrandr outputs all possible resolutions as it should.
When executing xrandr another time the 2415 switches back to 1024x768
Already tried kernel v3.18.3-vivid, no change.
Also tried Utopic live cd, no change.
Tried Windows 8.1, no issues with both screens. (however my main OS is Ubuntu
trusty, so..., just for testing)
ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: xorg 1:7.7+1ubuntu8
ProcVersionSignature: Ubuntu 3.13.0-44.73-generic 3.13.11-ckt12
Uname: Linux 3.13.0-44-generic x86_64
.tmp.unity.support.test.0:
ApportVersion: 2.14.1-0ubuntu3.6
Architecture: amd64
CompizPlugins: No value set for
`/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: compiz
CompositorUnredirectDriverBlacklist: '(nouveau|Intel).*Mesa 8.0'
CompositorUnredirectFSW: true
Date: Tue Jan 20 10:48:24 2015
DistUpgraded: Fresh install
DistroCodename: trusty
DistroVariant: ubuntu
DkmsStatus:
vboxhost, 4.3.20, 3.13.0-40-generic, x86_64: installed
vboxhost, 4.3.20, 3.13.0-43-generic, x86_64: installed
vboxhost, 4.3.20, 3.13.0-44-generic, x86_64: installed
ExtraDebuggingInterest: Yes
GraphicsCard:
Advanced Micro Devices, Inc. [AMD/ATI] Broadway XT [Mobility Radeon HD 5870]
[1002:68a0] (prog-if 00 [VGA controller])
Subsystem: Hewlett-Packard Company FirePro M7820 [103c:1520]
InstallationDate: Installed on 2014-05-11 (253 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140417)
MachineType: Hewlett-Packard HP EliteBook 8740w
PccardctlStatus:
Socket 0:
3.3V
16-bit
PC Card
Subdevice 0 (function 0) bound to driver "pata_pcmcia"
ProcKernelCmdLine: BOOT_IMAGE=/@trusty/boot/vmlinuz-3.13.0-44-generic
root=UUID=cfafe8f3-4766-4fc7-b6f3-857eefcd2aff ro rootflags=subvol=@trusty
plymouth:debug splash quiet drm.debug=0xe radeon.audio=1
SourcePackage: xorg
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 07/07/2014
dmi.bios.vendor: Hewlett-Packard
dmi.bios.version: 68CAD Ver. F.50
dmi.board.name: 1520
dmi.board.vendor: Hewlett-Packard
dmi.board.version: KBC Version 33.31
dmi.chassis.asset.tag: CNU1152Q9W
dmi.chassis.type: 10
dmi.chassis.vendor: Hewlett-Packard
dmi.modalias:
dmi:bvnHewlett-Packard:bvr68CADVer.F.50:bd07/07/2014:svnHewlett-Packard:pnHPEliteBook8740w:pvr:rvnHewlett-Packard:rn1520:rvrKBCVersion33.31:cvnHewlett-Packard:ct10:cvr:
dmi.product.name: HP EliteBook 8740w
dmi.sys.vendor: Hewlett-Packard
version.compiz: compiz 1:0.9.11.3+14.04.20141104-0ubuntu1
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.56-1~ubuntu1
version.libgl1-mesa-dri: libgl1-mesa-dri 10.1.3-0ubuntu0.2
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 10.1.3-0ubuntu0.2
version.xserver-xorg-core: xserver-xorg-core 2:1.15.1-0ubuntu2.6
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.8.2-1ubuntu2
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.3.0-1ubuntu3.1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.910-0ubuntu1.3
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.10-1ubuntu2
xserver.bootTime: Tue Jan 20 09:37:08 2015
xserver.configfile: /etc/X11/xorg.conf
xserver.errors:
xserver.logfile: /var/log/Xorg.0.log
xserver.version: 2:1.15.1-0ubuntu2.6
xserver.video_driver: radeon
** Affects: xorg (Ubuntu)
Importance: Undecided
Status: New
** Tags: amd64 apport-bug compiz-0.9 trusty ubuntu
--
You received this bug notification because you are a member of Ubuntu-X,
which is subscribed to xorg in Ubuntu.
https://bugs.launchpad.net/bugs/1412730
Title:
DELL U2415M monitor detection issues
To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1412730/+subscriptions
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