[HP ZBook 15] can not reduce brightness

[Martin Konôpka]

machine: HP ZBook 15
(Intel Core i7 4700MQ Haswell, NVIDIA Quadro K1100M 2GB, 1920 x 1080 display)

I go to the settings/Brightness & Lock section.
The button which should controll the screen brightness is on the right-hand side.
I move it to the left-hand side but nothing happens. The screen brightness remains to be 100% (too much for me).
The machine is running on the AC power cable.

The machine uses an intel graphics driver.

It contains also the NVidia card but that one is apparently inactive and the system did not offer me to install it.

ProblemType: Bug
DistroRelease: Ubuntu 13.10
Package: xserver-xorg-video-intel 2:2.99.904-0ubuntu2
ProcVersionSignature: Ubuntu 3.11.0-14.21-generic 3.11.7
Uname: Linux 3.11.0-14-generic x86_64
.tmp.unity.support.test.0:

ApportVersion: 2.12.5-0ubuntu2.1
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: Wed Dec 4 15:32:39 2013
DistUpgraded: Fresh install
DistroCodename: saucy
DistroVariant: ubuntu
ExtraDebuggingInterest: Yes
GraphicsCard:
 Intel Corporation 4th Gen Core Processor Integrated Graphics Controller [8086:0416] (rev 06) (prog-if 00 [VGA controller])
   Subsystem: Hewlett-Packard Company Device [103c:1909]
 NVIDIA Corporation GK107GLM [Quadro K1100M] [10de:0ff6] (rev a1) (prog-if 00 [VGA controller])
   Subsystem: Hewlett-Packard Company Device [103c:1909]
InstallationDate: Installed on 2013-12-04 (0 days ago)
InstallationMedia: Ubuntu 13.10 "Saucy Salamander" - Release amd64 (20131016.1)
MachineType: Hewlett-Packard HP ZBook 15
MarkForUpload: True
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.11.0-14-generic root=UUID=b1bd90e2-af55-4f94-a86e-ec16ca8b47e4 ro quiet splash vt.handoff=7
SourcePackage: xserver-xorg-video-intel
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 10/25/2013
dmi.bios.vendor: Hewlett-Packard
dmi.bios.version: L70 Ver. 01.06
dmi.board.name: 1909
dmi.board.vendor: Hewlett-Packard
dmi.board.version: KBC Version 94.47
dmi.chassis.type: 10
dmi.chassis.vendor: Hewlett-Packard
dmi.modalias: dmi:bvnHewlett-Packard:bvrL70Ver.01.06:bd10/25/2013:svnHewlett-Packard:pnHPZBook15:pvrA3009DD10303:rvnHewlett-Packard:rn1909:rvrKBCVersion94.47:cvnHewlett-Packard:ct10:cvr:
dmi.product.name: HP ZBook 15
dmi.product.version: A3009DD10303
dmi.sys.vendor: Hewlett-Packard
version.compiz: compiz 1:0.9.10+13.10.20131011-0ubuntu1
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.46-1ubuntu1
version.libgl1-mesa-dri: libgl1-mesa-dri 9.2.1-1ubuntu3
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 9.2.1-1ubuntu3
version.xserver-xorg-core: xserver-xorg-core 2:1.14.3-3ubuntu2
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.7.3-0ubuntu3.1
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.2.0-0ubuntu10
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.904-0ubuntu2
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.9-2ubuntu1
xserver.bootTime: Wed Dec 4 15:18:15 2013
xserver.configfile: default
xserver.errors:
 Failed to load module "nvidia" (module does not exist, 0)
 Failed to load module "nvidia" (module does not exist, 0)
 NOUVEAU(G0): [XvMC] Failed to initialize extension.
xserver.logfile: /var/log/Xorg.0.log
xserver.outputs:
 product id 4589
 vendor AUO
xserver.version: 2:1.14.3-3ubuntu2
---
ApportVersion: 2.12.7-0ubuntu6
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: ubuntu 2846 F.... pulseaudio
CasperVersion: 1.336ubuntu1
CurrentDesktop: Unity
DistroRelease: Ubuntu 14.04
LiveMediaBuild: Ubuntu 14.04 LTS "Trusty Tahr" - Alpha amd64 (20140109)
MachineType: Hewlett-Packard HP ZBook 15
MarkForUpload: True
Package: linux (not installed)
ProcFB:
 0 nouveaufb
 1 inteldrmfb
ProcKernelCmdLine: file=/cdrom/preseed/username.seed boot=casper initrd=/casper/initrd.lz quiet splash -- maybe-ubiquity
ProcVersionSignature: Ubuntu 3.13.0-1.16-generic 3.13.0-rc7
RelatedPackageVersions:
 linux-restricted-modules-3.13.0-1-generic N/A
 linux-backports-modules-3.13.0-1-generic N/A
 linux-firmware 1.119
Tags: trusty
Uname: Linux 3.13.0-1-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo
dmi.bios.date: 10/25/2013
dmi.bios.vendor: Hewlett-Packard
dmi.bios.version: L70 Ver. 01.06
dmi.board.name: 1909
dmi.board.vendor: Hewlett-Packard
dmi.board.version: KBC Version 94.47
dmi.chassis.type: 10
dmi.chassis.vendor: Hewlett-Packard
dmi.modalias: dmi:bvnHewlett-Packard:bvrL70Ver.01.06:bd10/25/2013:svnHewlett-Packard:pnHPZBook15:pvrA3009DD10303:rvnHewlett-Packard:rn1909:rvrKBCVersion94.47:cvnHewlett-Packard:ct10:cvr:
dmi.product.name: HP ZBook 15
dmi.product.version: A3009DD10303
dmi.sys.vendor: Hewlett-Packard
---
ApportVersion: 2.12.7-0ubuntu6
Architecture: amd64
CasperVersion: 1.336ubuntu1
CurrentDesktop: Unity
DistUpgraded: Fresh install
DistroCodename: trusty
DistroRelease: Ubuntu 14.04
DistroVariant: ubuntu
LiveMediaBuild: Ubuntu 14.04 LTS "Trusty Tahr" - Alpha amd64 (20140109)
MachineType: Hewlett-Packard HP ZBook 15
MarkForUpload: True
Package: xserver-xorg-input-evdev 1:2.8.2-1ubuntu1
PackageArchitecture: amd64
ProcKernelCmdLine: file=/cdrom/preseed/username.seed boot=casper initrd=/casper/initrd.lz quiet splash -- maybe-ubiquity
ProcVersionSignature: Ubuntu 3.13.0-1.16-generic 3.13.0-rc7
Tags: trusty ubuntu reproducible has-workaround
Uname: Linux 3.13.0-1-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo
dmi.bios.date: 10/25/2013
dmi.bios.vendor: Hewlett-Packard
dmi.bios.version: L70 Ver. 01.06
dmi.board.name: 1909
dmi.board.vendor: Hewlett-Packard
dmi.board.version: KBC Version 94.47
dmi.chassis.type: 10
dmi.chassis.vendor: Hewlett-Packard
dmi.modalias: dmi:bvnHewlett-Packard:bvrL70Ver.01.06:bd10/25/2013:svnHewlett-Packard:pnHPZBook15:pvrA3009DD10303:rvnHewlett-Packard:rn1909:rvrKBCVersion94.47:cvnHewlett-Packard:ct10:cvr:
dmi.product.name: HP ZBook 15
dmi.product.version: A3009DD10303
dmi.sys.vendor: Hewlett-Packard
version.compiz: compiz 1:0.9.10+13.10.20131011-0ubuntu1
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.50-1
version.libgl1-mesa-dri: libgl1-mesa-dri 10.0.1-1ubuntu2
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 10.0.1-1ubuntu2
version.xserver-xorg-core: xserver-xorg-core 2:1.14.5-1ubuntu2
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.8.2-1ubuntu1
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.2.0-0ubuntu10
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.907-0ubuntu1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.10-1ubuntu1
xserver.bootTime: Thu Jan 9 17:28:35 2014
xserver.configfile: default
xserver.errors:
 Failed to load module "nvidia" (module does not exist, 0)
 Failed to load module "nvidia" (module does not exist, 0)
 NOUVEAU(G0): [XvMC] Failed to initialize extension.
xserver.logfile: /var/log/Xorg.0.log
xserver.outputs:
 product id 4589
 vendor AUO
xserver.version: 2:1.14.5-1ubuntu2

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[ebutler (ebutler)]

Also affects me on the Zbook 14

[penalvch (penalvch)]

Martin Konopka, this bug was reported a while ago and there hasn't been any activity in it recently. We were wondering if this is still an issue? If so, could you please test for this with the latest development release of Ubuntu? ISO images are available from http://cdimage.ubuntu.com/daily-live/current/ .

If it remains an issue, could you please run the following command in the development release from a Terminal (Applications->Accessories->Terminal), as it will automatically gather and attach updated debug information to this report:

apport-collect -p linux REPLACE-WITH-BUG-NUMBER

Please note, given that the information from the prior release is already available, doing this on a release prior to the development one would not be helpful.

If reproducible, could you also please test the latest upstream kernel available (not the daily folder) following https://wiki.ubuntu.com/KernelMainlineBuilds ? It will allow additional upstream developers to examine the issue. Once you've tested the upstream kernel, please comment on which kernel version specifically you tested. If this bug is fixed in the mainline kernel, please add the following tags:
kernel-fixed-upstream
kernel-fixed-upstream-VERSION-NUMBER

where VERSION-NUMBER is the version number of the kernel you tested. For example:
kernel-fixed-upstream-v3.13-rc7

This can be done by clicking on the yellow circle with a black pencil icon next to the word Tags located at the bottom of the bug description. As well, please remove the tag:
needs-upstream-testing

If the mainline kernel does not fix this bug, please add the following tags:
kernel-bug-exists-upstream
kernel-bug-exists-upstream-VERSION-NUMBER

As well, please remove the tag:
needs-upstream-testing

Once testing of the upstream kernel is complete, please mark this bug's Status as Confirmed. Please let us know your results. Thank you for your understanding.

[Martin Konôpka (martin.konopka)]

Yes, it is still an issue on ubuntu 13.10. (No proprietary NVidia driver installed.) I will test the problem on the latest development version of ubuntu.

The issue is worse than you might expect. I often need to read and edit documents and those use a white background (typically PDF documents). The brightness is so high that it turns the notebook almost unusable for me.

Please note that the HP ZBook series is rather new (selling started about September 2013) and this might be the reason why not so many people complain about the brightness bug. Nevertheless, the other user confirmed the issue very recently (25th December).

[ebutler (ebutler)]

I can confirm this problem still persists also.

Martin -- I hacked this workaround, that maybe can work for you too.

I mapped
'sudo /home/ebutler/bin/backlight.sh up'
to Ctrl-F10 (my backlight is Fn-F10) using the keyboard shortcut options,
and added
ebutler ALL=(ALL) NOPASSWD: /home/ebutler/bin/backlight.sh
to /etc/sudoers

and it works pretty well. Maybe you have to tweak the $BACKLIGHT_DIR or something to make it work. I'm using the Intel adapter.

[penalvch (penalvch)]

ebutler, thank you for your comment. So your hardware and problem may be tracked, could you please file a new report by executing the following in a terminal:
ubuntu-bug xorg

For more on this, please see the official Ubuntu documentation:
Ubuntu X.Org Team, Ubuntu Bug Control, and Ubuntu Bug Squad: https://wiki.ubuntu.com/Bugs/BestPractices#X.2BAC8-Reporting.Focus_on_One_Issue
Ubuntu Community: https://help.ubuntu.com/community/ReportingBugs#Bug_reporting_etiquette

When opening up the new report, please feel free to subscribe me to it.

Please note, not filing a new report will delay your problem being addressed as quickly as possible.

Thank you for your understanding.

[Martin Konôpka (martin.konopka)]

ebutler, thanks for the workaround, I will try it.

In the meantime I tested at least the live version of the latest development version of ubuntu
(trusty-desktop-amd64.iso 09-Jan-2014 07:51 910M)
and found the same bug also there.

I am going to update the report according to what I was asked above.
However, I think I will not try the latest kernel at the moment. I think that if the bug is really in xorg, then using a different kernel would not help. (If I am wrong please notify me and if really needed I will install the development version of ubuntu on the hard drive and will test also the kernel.)

[Martin Konôpka (martin.konopka)]

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[Martin Konôpka (martin.konopka)]

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[Martin Konôpka (martin.konopka)]

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[Martin Konôpka (martin.konopka)]

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[Martin Konôpka (martin.konopka)]

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[Martin Konôpka (martin.konopka)]

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[Martin Konôpka (martin.konopka)]

I am really sorry for my 2nd apport information concerning the package
xserver-xorg-input-evdev
on the latest development version.

It should have been attached to the bug 662933 (keyboard mapping mixed up upon pressing NumLock).
I did the mistake and attached it to the present bug.

Should I re-run the apport-collect with the correct bug number?

[Martin Konôpka (martin.konopka)]

Hello ebutler,

I tried your script but it did not work for me. Of course I changed the paths to match my login name konopka.
The script did not modify the brightness even when I run it directly from command line (using sudo).
However, I was not surprised by it because there is no command for xserver in the script.

My impression is that you attached only a starting fragment of the whole script. The only thing done by the script is to modify the content of the file
$BACKLIGHT_DIR/brightness
The value of the variable BRIGHTNESS is set in a bash session but it is forgot immediately and is not transferred to the xserver.

What I would expect from such a script is to force the xserver to read the numerical value written to file
$BACKLIGHT_DIR/brightness
and then xserver (at least in my naive imagination) should finally change the screen brightness.
However, I am not an expert and I do not know how to force the xserver to do such a thing. I checked "man xorg" and found that the entire manual page did not contain any string with "bright".

[ebutler (ebutler)]

Oh, sorry, I missed out an important step, my $HOME/backlight directory is a link to /sys/class/backlight/intel_backlight. You should either do the same or change $BACKLIGHT_DIR to the same thing, and then the brightness should get updated instantly when you run the script (no need for calling any xserver commands)

[Barney (barney-b)]

I have the same problem with a ZBook 14 with Intel/AMD graphics. My current workaround is to use this script (which is actually what I use on my desktop at night):

#!/bin/bash
xrandr -q | grep " connected" | awk '{print $1}' | while read d; do
  echo "setting $d"
  xrandr --output $d --brightness $1
done

Then just call "set-brightness 0.6" for 60% etc. This doesn't bind to the F9 / F10 buttons, but does the trick.

HTH

[penalvch (penalvch)]

ebutler / Barney, thank you for your comment. So your hardware and problem may be tracked, could you please file a new report with Ubuntu by executing the following in a terminal while booted into a Ubuntu repository kernel (not a mainline one) via:
ubuntu-bug linux

For more on this, please read the official Ubuntu documentation:
Ubuntu Bug Control and Ubuntu Bug Squad: https://wiki.ubuntu.com/Bugs/BestPractices#X.2BAC8-Reporting.Focus_on_One_Issue
Ubuntu Kernel Team: https://wiki.ubuntu.com/KernelTeam/KernelTeamBugPolicies#Filing_Kernel_Bug_reports
Ubuntu Community: https://help.ubuntu.com/community/ReportingBugs#Bug_reporting_etiquette

When opening up the new report, please feel free to subscribe me to it.

Thank you for your understanding.

Helpful bug reporting tips:
https://wiki.ubuntu.com/ReportingBugs

[Martin Konôpka (martin.konopka)]

It now became possible to boot a live DVD of the latest development release of ubuntu (64 bit) on my HP ZBook. I installed this system of the machine's HDD. I have applied all available updates via the UpdateManager.

The brightenss problem remains.

Afterwards I tested also the latest mainline kernel, i.e. file
linux-image-3.13.1-031301-generic_3.13.1-031301.201401291035_amd64.deb
(Of course, I rebooted the machine after having the kernel installed.)
Even with the newest kernel it remains impossible to controll brightness using the tool in the Control Centre.
The other "official" way to control brightness should be the Fn F9 and Fn F10 key combinations. I can see that pressing _either_ of these key pairs has the effect of immediate maximisation of brightness. No way to decrease it.

I can still controll brightness (fortunatelly) using the workaround proposed by ebutler (see above). In its essence it is done by variation of the number written in file
/sys/class/backlight/intel_backlight/brightness
I my opinion this bug should be easy to fix bacause it looks to be only the issue of the desktop environment.

BTW, even if I set brightness to an acceptably low value for me, it remains at this value only untill the screensaver is started. Pressing a key (to cancel the screensaver) turns the brighteness to its maximum.

[Martin Konôpka (martin.konopka)]

The latest mainline kernel 3.14.0-031400rc2-generic fixed the bug. I can now controll brightness both using the Control Center and also the Fn F9 and Fn F10 key strokes. I added appropriate tags to the bug.

[Martin Konôpka (martin.konopka)]

The fix is not perfect: the machine (running kernel v3.14.0-031400rc2-generic) does not remember the user-set value of the brightness. After reboot the brightness is set on its maximum.

[madbiologist (me-again)]

The fix in the upstream 3.14-rc2 kernel has been removed and replaced with a better one in the upstream 3.14-rc4 kernel by these two commits:

commit bd8ba20597f0cfef3ef65c3fd2aa92ab23d4c8e1 - ACPI / video: Filter the _BCL table for duplicate brightness values
commit 0e9f81d3b7cd0649a3bc437391b6a0650f98f844 - ACPI / video: Add systems that should favour native backlight interface

and this one:

author Rafael J. Wysocki
committer Rafael J. Wysocki
commit a6940190ac15c361862a1a8f50a2072db7184749
tree c73be15646c6418f77a94fede3afc7eabd589dd6
parent 0e9f81d3b7cd0649a3bc437391b6a0650f98f844

Revert "ACPI: Blacklist Win8 OSI for some HP laptop 2013 models"

This reverts commit 2d4054d84224 (ACPI: Blacklist Win8 OSI for some HP laptop 2013 models) that is not necessary any more after previous commit 1811fcb029fa (ACPI / video: Add systems that should favour native backlight interface).

Requested-by: Takashi Iwai
Tested-by: Mika Westerberg
Signed-off-by: Rafael J. Wysocki

The first one has been cc'd to the stable kernel series. A PPA of the 3.14-rc4 kernel is available at http://kernel.ubuntu.com/~kernel-ppa/mainline/ and instructions on how to install and uninstall it are available at https://wiki.ubuntu.com/Kernel/MainlineBuilds

[Paolo Montrasio (paolo-paolomontrasio)]

I have this problem on a HP Zbook 15 with kernel 3 .11.0-17-generic #31~precise1-Ubuntu SMP Tue Feb 4 21:25:43 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux
However if I use KDE the keyboard controls change the screen brightness. It seems it's not only a kernel matter.
It's KDE 4.8.5.

[penalvch (penalvch)]

Paolo Montrasio, thank you for your comment. So your hardware and problem may be tracked, could you please file a new report with Ubuntu by executing the following in a terminal while booted into a Ubuntu repository kernel (not a mainline one) via:
ubuntu-bug linux

For more on this, please read the official Ubuntu documentation:
Ubuntu Bug Control and Ubuntu Bug Squad: https://wiki.ubuntu.com/Bugs/BestPractices#X.2BAC8-Reporting.Focus_on_One_Issue
Ubuntu Kernel Team: https://wiki.ubuntu.com/KernelTeam/KernelTeamBugPolicies#Filing_Kernel_Bug_reports
Ubuntu Community: https://help.ubuntu.com/community/ReportingBugs#Bug_reporting_etiquette

When opening up the new report, please feel free to subscribe me to it.

Thank you for your understanding.

Helpful bug reporting tips:
https://wiki.ubuntu.com/ReportingBugs

[Paolo Montrasio (paolo-paolomontrasio)]

Christopher, I'll try to do that after I understand what it means being booted up into a "Ubuntu repository kernel (not a mainline one)". I'll read the pages you linked.

Meanwhile I'd like to point out that a proper workaround is to use xbacklight -set NNN (0 to 100) and not xrandr as in the comments above. According to the xrand man page:

--brightness brightness
              Multiply the gamma values on the crtc currently attached to the output to specified
              floating value. Useful for overly bright or overly dim outputs. However, this is a
              software only modification, if your hardware has support to actually change the
              brightness, you will probably prefer to use xbacklight.

It's not installed by default.
sudo apt-get install xbacklight

xbacklight works fine on my hardware. The problem is only with the Fn F9/F10 keys (and the brightness slider in the settings too). Thet don't change the backlight despite changing the brightness indicator in the gnome popup (I'm back to gnome as I found workarounds to other issues I had). As those keys work in KDE I suspect that we are facing two different problems:

1) A kernel one that applies to other commenteers but not to me. Does xbacklight work for them?
2) A gnome one that applies to me: it seems it's not making the right calls in response to Fn F9/F10. KDE does.

[Martin Konôpka (martin.konopka)]

Paolo, "Ubuntu repository kernel (not a mainline one)" is, I guess, just the default kernel you get in ubuntu system.

[Barney (barney-b)]

Yep - I'd seen the man page for xrandr, but xbacklight has no effect on my hardware, which is why I used xrandr. I guess as far as the workarounds go, just use whatever works for you. Cheers.

[Logan Browne (y-logan)]

I have the backlight control keys working on 3.13.0-17 with the addition of the following to my /etc/default/grub file:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=vendor"

The backlight is controlled through the intel driver rather because the internal display is connected to that card rather than the nvidia.

$uname -a
Linux lcb-zbook-15 3.13.0-17-generic #37-Ubuntu SMP Mon Mar 10 21:44:01 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux

[stratos (stratosgear)]

After following all the proposed solutions in the thread, I have to verify that the solution proposed in #58 is what worked for me.

I am running on a HP Zbook 15.

$ uname -a
Linux firefly 3.11.0-12-generic #19-Ubuntu SMP Wed Oct 9 16:20:46 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux

[Martin Konôpka (martin.konopka)]

During about last mont the bug did not show itself. Hence I changed the status to Fix released. However, a related problem remains which I am going to report separately.

[Paolo Montrasio (paolo-paolomontrasio)]

I tried the fix reported by #58 but it didn't work. Before that Fn LumUp/Down displayed the brightness control overlay. After that it didn't show it anymore. I restored the original boot configuration and it appears again. Unfortunately Shutdown behaves like Restart now. I remember I had the same problem when I installed the ZBook but it went away after I installed KUbuntu (but I went back to Gnome session fallback later on.)

$ lsb_release -a
LSB Version: core-2.0-amd64:core-2.0-noarch:core-3.0-amd64:core-3.0-noarch:core-3.1-amd64:core-3.1-noarch:core-3.2-amd64:core-3.2-noarch:core-4.0-amd64:core-4.0-noarch
Distributor ID: Ubuntu
Description: Ubuntu 12.04.5 LTS
Release: 12.04
Codename: precise

$ uname -a
Linux *** 3.13.0-48-generic #80~precise1-Ubuntu SMP Thu Mar 12 19:30:15 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux