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[SOLVED] Task bar disappears + no Alt-Tab function

Posted:
Jul 23rd, '12, 03:38
by Myles
Okay this has just happened to me again - for a about the 7th or 8th time now in the past few weeks. This first happened a few weeks ago about 10 minutes or so after a bunch of updates were applied (I can't rememnber what they were though). What happens is that I amdoing something - web surfing, creating/ed a documentin LibreOfficeand all of a sudden my screen "changes" i.e. know somethig has just happened; my task bar has disappeared and there is no Alt-Tab functionality between open windows/applications. The window that has focus is still active and I still have mouse movement but not much else. The only way this novice can get out of it is to Ctrl-Alt-Backspace to logout and log back in and all is normal again. I have not identified that I have been doing anything 'in particular' to trigger this problem.
Has anyone else experienced this sort of behaviour or is it something unique to my system?? Mageia #2, 32 Bit.
Any help/direction appreciated.
Re: Task bar disappears + no Alt-Tab function

Posted:
Jul 23rd, '12, 04:12
by jtmh
I've never experienced that. Maybe you can look into some system log files, e.g., /var/log/messages, and try finding if there are any errors at the time when you experienced that situation.
Re: Task bar disappears + no Alt-Tab function

Posted:
Jul 23rd, '12, 08:43
by mk
The only time I enountered something like this was in Gnome2 with native metacity compositing and Nvidia drivers. From time to time, taskbar disappeared. No known workaround other then not using Nvidia drivers.
I don't know what WM/DE you use, but trying to temporarily disable compositing cannot harm.

Re: Task bar disappears + no Alt-Tab function

Posted:
Jul 24th, '12, 05:50
by Myles
Whoops, should have mentioned that I use KDE -D'OH! I also have an old GeForce FX series card and in MCC it looks like I am using the nVidia driver of some sort! I didn't think that my card was supported anymore under the new nVidia driver and that I was using noveau. I know that I had trouble installing Mageia due to my nVidia card - during the install process I had to chose Vesa as the driver to successfully install. Prior to whatever updates that were applied just before the first incident (maybe it was just a coincidence????) my system had been stable.
Re: Task bar disappears + no Alt-Tab function

Posted:
Jul 24th, '12, 06:56
by Myles
Okay, it just happened again! This time (and I think the previous time it happened) I was in LibreOffice Writer, just saved a document and was priniting it out - which IIRC was what I was doing when it last happened. So the plot thickens.
Re: Task bar disappears + no Alt-Tab function

Posted:
Jul 24th, '12, 07:33
by djennings
Are there any issues with memory? Is your swap space filling up, or perhaps there is a kernel oops in the syslog?
Re: Task bar disappears + no Alt-Tab function

Posted:
Jul 25th, '12, 11:17
by benmc
I also have a very similar problem [ mageia2, 32 bit,dm=kde, geforce video card ,ps/2 mouse ] but for me also locks out keyboard [ wired ] .
occurence is irregular but for me happens when browsing [ firefox ] while file copy [ eg, to usb ] and transcoding video clip [ kdenlive ] .
may happen 2-3 times in an hr but then may not recur again for days!!!!
have waited 1/2 hr after atempting to close applications [ away from keyboard for a while ]. have to reboot and go back to M1 for a while
regards
Re: Task bar disappears + no Alt-Tab function

Posted:
Jul 25th, '12, 12:16
by tom_
as djennings sugegsted, it could be useful too see some log.
when the problem happens, please open konsole (or switch to a console by pressing CTRL-ALT-F1),
then type
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tail -n 200 /var/log/syslog > myfile.txt
and report here the contents of the file myfile.txt when possible
Re: Task bar disappears + no Alt-Tab function

Posted:
Jul 25th, '12, 21:38
by hocico0777
Exactly same problem,happened twice 3 days ago when pressed the save button in libre office writer (not only in libre office).
Re: Task bar disappears + no Alt-Tab function

Posted:
Jul 25th, '12, 22:13
by benmc
thanks for reply.
for me, difficult to check the log when the keyboard is locked out and reboot is required. [ no offense meant ]
regards
Re: Task bar disappears + no Alt-Tab function

Posted:
Jul 26th, '12, 01:21
by Myles
Thanksfor that. I will get into the syslog next time it happens and post results.
Re: Task bar disappears + no Alt-Tab function

Posted:
Jul 26th, '12, 01:28
by Ken-Bergen
benmc wrote:thanks for reply.
for me, difficult to check the log when the keyboard is locked out and reboot is required. [ no offense meant ]
regards
Sometimes but not always unplugging the keyboard and plugging it back in works.
Re: Task bar disappears + no Alt-Tab function

Posted:
Jul 26th, '12, 01:38
by tom_
benmc wrote:for me, difficult to check the log when the keyboard is locked out and reboot is required. [ no offense meant ]
correct

however /var/log/syslog.log is a file,
you can reboot and then search the relevant lines in it,
look the lines before the reboot
Re: Task bar disappears + no Alt-Tab function

Posted:
Jul 26th, '12, 18:02
by doktor5000
FWIW, this sounds like plasma crashing, maybe due to problems with nouveau, which is rather crashy.
Please show the output of
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grep -Ri driver /var/log/Xorg.0.log
Is this a fresh Mageia 2 installation and a fresh /home or is this some upgrade from Mageia 1 or Mandriva, or maybe an old /home?
Re: Task bar disappears + no Alt-Tab function

Posted:
Jul 26th, '12, 18:16
by hocico0777
In my case i have the proprietary driver and not nouveau.Also i made a clean install but kept the old home partition from the opensuse installation (kde also).
During the first weeks with mageia 2 i do not remember this problem happening but sometimes ithink that also the whole desktop 'freezes' for a few seconds until it becomes responsive again.
Re: Task bar disappears + no Alt-Tab function

Posted:
Jul 26th, '12, 18:43
by doktor5000
hocico0777 wrote:In my case i have the proprietary driver and not nouveau.Also i made a clean install but kept the old home partition from the opensuse installation (kde also).
How did you find out or see that you're currently definitely using nvidia driver?
Also, for the old settings from that opensuse installation, please try again with a freshly created user to rule out problem with old settings.
Re: Task bar disappears + no Alt-Tab function

Posted:
Jul 26th, '12, 18:57
by hocico0777
doktor5000 wrote:hocico0777 wrote:In my case i have the proprietary driver and not nouveau.Also i made a clean install but kept the old home partition from the opensuse installation (kde also).
How did you find out or see that you're currently definitely using nvidia driver?
Also, for the old settings from that opensuse installation, please try again with a freshly created user to rule out problem with old settings.
Because it was the first thing to do after the mageia installation.
Could you remind me how to create a new user account?
Re: Task bar disappears + no Alt-Tab function

Posted:
Jul 26th, '12, 23:26
by doktor5000
Maybe you misunderstood, i just want to know how exactly you verified which driver you are using.
You know, installing it and switching to it are one thing, if the system really uses it next time it boots or that there were no mistakes in the process and everything worked properly are two different stories. So please show the output of
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grep -Ri driver /var/log/Xorg.0.log
For a new user, either in a terminal via
- Code: Select all
useradd -m name_of_new_user
or in MCC (Mageia Control Center) under System -> Manage users on system (which can also be called in a terminal directly as userdrake or drakuser, and there just click on
Add user
Re: Task bar disappears + no Alt-Tab function

Posted:
Jul 27th, '12, 02:35
by Myles
Okay, sorry I have missed all the recent activity on this subject. I did a clean install of Mageia #2and just copied my backed-up data back into my Home folder.
The reseultsof the driver queryis that I am using Noveau:
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myles@Bilbo Downloads]$ grep -Ri driver /var/log/Xorg.0.log
[ 42.762] X.Org Video Driver: 11.0
[ 42.762] X.Org XInput driver : 13.0
[ 43.214] (II) Loading /usr/lib/xorg/modules/drivers/v4l_drv.so
[ 43.215] ABI class: X.Org Video Driver, version 11.0
[ 43.222] (II) Loading /usr/lib/xorg/modules/drivers/nouveau_drv.so
[ 43.223] Module class: X.Org Video Driver
[ 43.223] ABI class: X.Org Video Driver, version 11.0
[ 43.223] (II) v4l driver for Video4Linux
[ 43.223] (II) NOUVEAU driver
[ 43.223] (II) NOUVEAU driver for NVIDIA chipset families :
[ 43.225] (II) Loading /usr/lib/xorg/modules/drivers/nouveau_drv.so
[ 43.383] (**) NOUVEAU(0): Driver mode "1920x1080": 173.0 MHz (scaled from 0.0 MHz), 67.2 kHz, 60.0 Hz
[ 43.383] (**) NOUVEAU(0): Driver mode "1680x1050": 146.2 MHz (scaled from 0.0 MHz), 65.3 kHz, 60.0 Hz
[ 43.383] (**) NOUVEAU(0): Driver mode "1280x1024": 135.0 MHz (scaled from 0.0 MHz), 80.0 kHz, 75.0 Hz
[ 43.383] (**) NOUVEAU(0): Driver mode "1280x1024": 108.0 MHz (scaled from 0.0 MHz), 64.0 kHz, 60.0 Hz
[ 43.383] (**) NOUVEAU(0): Driver mode "1440x900": 136.8 MHz (scaled from 0.0 MHz), 70.6 kHz, 75.0 Hz
[ 43.383] (**) NOUVEAU(0): Driver mode "1440x900": 106.5 MHz (scaled from 0.0 MHz), 55.9 kHz, 59.9 Hz
[ 43.383] (**) NOUVEAU(0): Driver mode "1280x960": 108.0 MHz (scaled from 0.0 MHz), 60.0 kHz, 60.0 Hz
[ 43.383] (**) NOUVEAU(0): Driver mode "1280x800": 83.5 MHz (scaled from 0.0 MHz), 49.7 kHz, 59.8 Hz
[ 43.384] (**) NOUVEAU(0): Driver mode "1152x864": 108.0 MHz (scaled from 0.0 MHz), 67.5 kHz, 75.0 Hz
[ 43.384] (**) NOUVEAU(0): Driver mode "1024x768": 78.8 MHz (scaled from 0.0 MHz), 60.1 kHz, 75.1 Hz
[ 43.384] (**) NOUVEAU(0): Driver mode "1024x768": 65.0 MHz (scaled from 0.0 MHz), 48.4 kHz, 60.0 Hz
[ 43.384] (**) NOUVEAU(0): Driver mode "832x624": 57.3 MHz (scaled from 0.0 MHz), 49.7 kHz, 74.6 Hz
[ 43.384] (**) NOUVEAU(0): Driver mode "800x600": 49.5 MHz (scaled from 0.0 MHz), 46.9 kHz, 75.0 Hz
[ 43.384] (**) NOUVEAU(0): Driver mode "800x600": 40.0 MHz (scaled from 0.0 MHz), 37.9 kHz, 60.3 Hz
[ 43.384] (**) NOUVEAU(0): Driver mode "640x480": 31.5 MHz (scaled from 0.0 MHz), 37.5 kHz, 75.0 Hz
[ 43.384] (**) NOUVEAU(0): Driver mode "640x480": 25.2 MHz (scaled from 0.0 MHz), 31.5 kHz, 60.0 Hz
[ 43.384] (**) NOUVEAU(0): Driver mode "720x400": 28.3 MHz (scaled from 0.0 MHz), 31.5 kHz, 70.1 Hz
[ 43.386] ABI class: X.Org Video Driver, version 11.0
[ 43.388] (II) NOUVEAU(0): [DRI2] DRI driver: nouveau
[ 43.388] (II) NOUVEAU(0): [DRI2] VDPAU driver: nouveau
[ 43.410] (II) EXA(0): Driver allocated offscreen pixmaps
[ 43.410] (II) EXA(0): Driver registered support for the following operations:
[ 45.231] Module class: X.Org XInput Driver
[ 45.231] ABI class: X.Org XInput driver, version 13.0
[ 45.231] (II) Using input driver 'evdev' for 'Power Button'
[ 45.264] (II) Using input driver 'evdev' for 'Power Button'
[ 45.266] (II) Using input driver 'evdev' for 'AT Translated Set 2 keyboard'
[ 45.267] (II) Using input driver 'evdev' for 'GenPS/2 Genius Mouse'
[ 45.268] (II) No input driver specified, ignoring this device.
Re: Task bar disappears + no Alt-Tab function

Posted:
Jul 27th, '12, 13:50
by hocico0777
the output of grep -Ri driver /var/log/Xorg.0.log is the following
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bash-4.2$ grep -Ri driver /var/log/Xorg.0.log
[ 15.719] X.Org Video Driver: 11.0
[ 15.719] X.Org XInput driver : 13.0
[ 15.814] (II) Loading /usr/lib/xorg/modules/drivers/v4l_drv.so
[ 15.815] ABI class: X.Org Video Driver, version 11.0
[ 16.291] Module class: X.Org Video Driver
[ 16.291] (II) v4l driver for Video4Linux
[ 16.291] (II) NVIDIA dlloader X Driver 295.49 Mon Apr 30 23:31:55 PDT 2012
[ 16.291] (II) NVIDIA Unified Driver for all Supported NVIDIA GPUs
[ 18.417] (II) NVIDIA(0): [DRI2] VDPAU driver: nvidia
[ 18.490] Module class: X.Org XInput Driver
[ 18.490] ABI class: X.Org XInput driver, version 13.0
[ 18.490] (II) Using input driver 'evdev' for 'Power Button'
[ 18.512] (II) Using input driver 'evdev' for 'Power Button'
[ 18.512] (II) Using input driver 'evdev' for 'Logitech USB Receiver'
[ 18.513] (II) Using input driver 'evdev' for 'Logitech USB Receiver'
[ 18.514] (II) No input driver specified, ignoring this device.
[ 18.514] (II) Using input driver 'evdev' for 'UVC Camera (046d:0825)'
[ 18.514] (II) No input driver specified, ignoring this device.
[ 18.515] (II) No input driver specified, ignoring this device.
[ 18.515] (II) No input driver specified, ignoring this device.
[ 18.515] (II) No input driver specified, ignoring this device.
[ 18.515] (II) No input driver specified, ignoring this device.
[ 18.515] (II) No input driver specified, ignoring this device.
[ 18.516] (II) No input driver specified, ignoring this device.
[ 18.516] (II) No input driver specified, ignoring this device.
bash-4.2$
Re: Task bar disappears + no Alt-Tab function

Posted:
Jul 27th, '12, 18:27
by hocico0777
Problem occurs for a new user also.
Re: Task bar disappears + no Alt-Tab function

Posted:
Jul 27th, '12, 21:31
by doktor5000
Re: Task bar disappears + no Alt-Tab function

Posted:
Jul 28th, '12, 04:41
by Myles
doktor, unfortunately my card is too old and now is not supported inthe latest nVidia driver, so I'll have to stik with noveau it seems.
Re: Task bar disappears + no Alt-Tab function

Posted:
Jul 28th, '12, 09:16
by Myles
Okay, and it happened again about 4:16 pm - this time I was going through my extensive music collection moving stuff around in Dolphin when it happened. Now back up and running- with a break to take the washing off the line - so here is the relevant lines of the syslog around that time:
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Jul 28 16:09:03 Bilbo sensord: Chip: acpitz-virtual-0
Jul 28 16:09:03 Bilbo sensord: Adapter: Virtual device
Jul 28 16:09:03 Bilbo sensord: temp1: 21.8 C
Jul 28 16:15:11 Bilbo mgaapplet[2545]: Computing new updates...
Jul 28 16:15:11 Bilbo mgaapplet[2545]: running: urpmi.update --update
Jul 28 16:15:13 Bilbo mgaapplet[2545]: updating inactive backport media Core Backports Testing (distrib9), Nonfree Backports Testing (distrib19), Tainted Backports Testing (distrib29)
Jul 28 16:15:13 Bilbo mgaapplet[2545]: running: urpmi.update Core Backports Testing (distrib9)
Jul 28 16:15:14 Bilbo mgaapplet[2545]: running: urpmi.update Nonfree Backports Testing (distrib19)
Jul 28 16:15:15 Bilbo mgaapplet[2545]: running: urpmi.update Tainted Backports Testing (distrib29)
Jul 28 16:15:16 Bilbo mgaapplet[2545]: Packages are up to date
The next line after these is after I had logged off and back on again, with a time-stamp of 16:29
Re: Task bar disappears + no Alt-Tab function

Posted:
Jul 28th, '12, 10:34
by Myles
Folks, I have to send more of the syslog data as I have just noticed that the time that I thought that this happened (going by my watch)amybe completely out by half an hour as I just noticedthat my watch was about 20mins behind what the actualtime is!
so here is a bit more after the point I posted above:
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Jul 28 16:29:03 Bilbo sensord: Chip: acpitz-virtual-0
Jul 28 16:29:03 Bilbo sensord: Adapter: Virtual device
Jul 28 16:29:03 Bilbo sensord: temp1: 21.8 C
Jul 28 16:37:42 Bilbo mgaapplet[2545]: Received SIGHUP (probably an upgrade has finished), restarting applet.
Jul 28 16:37:43 Bilbo kdm[730]: X server for display :0 terminated unexpectedly
Jul 28 16:37:43 Bilbo acpid: client 812[0:0] has disconnected
Jul 28 16:37:43 Bilbo acpid: client connected from 12615[0:0]
Jul 28 16:37:43 Bilbo acpid: 1 client rule loaded
Jul 28 16:37:51 Bilbo kdm: :0 '[12665]: Session log file according to cannot be created: No such file or directory
Jul 28 16:37:53 Bilbo dbus-daemon[727]: dbus[727]: [system] Activating service name='org.kde.powerdevil.backlighthelper' (using servicehelper)
Jul 28 16:37:53 Bilbo dbus[727]: [system] Activating service name='org.kde.powerdevil.backlighthelper' (using servicehelper)
Jul 28 16:37:53 Bilbo dbus-daemon[727]: no kernel backlight interface found
Jul 28 16:37:53 Bilbo dbus-daemon[727]: dbus[727]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Jul 28 16:37:53 Bilbo dbus[727]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Jul 28 16:38:01 Bilbo rtkit-daemon[2328]: Successfully made thread 12883 of process 12883 (/usr/bin/pulseaudio) owned by '500' high priority at nice level -11.
Jul 28 16:38:01 Bilbo rtkit-daemon[2328]: Supervising 1 threads of 1 processes of 1 users.
Jul 28 16:38:01 Bilbo pulseaudio[12883]: [pulseaudio] pid.c: Stale PID file, overwriting.
Jul 28 16:38:01 Bilbo pulseaudio[12883]: [pulseaudio] sink.c: Default and alternate sample rates are the same.
Jul 28 16:38:01 Bilbo rtkit-daemon[2328]: Successfully made thread 12884 of process 12883 (/usr/bin/pulseaudio) owned by '500' RT at priority 5.
Jul 28 16:38:01 Bilbo rtkit-daemon[2328]: Supervising 2 threads of 1 processes of 1 users.
Jul 28 16:38:01 Bilbo rtkit-daemon[2328]: Successfully made thread 12885 of process 12883 (/usr/bin/pulseaudio) owned by '500' RT at priority 5.
Jul 28 16:38:01 Bilbo rtkit-daemon[2328]: Supervising 3 threads of 1 processes of 1 users.
Jul 28 16:38:24 Bilbo rtkit-daemon[2328]: Successfully made thread 13087 of process 13087 (/usr/bin/pulseaudio) owned by '500' high priority at nice level -11.
Jul 28 16:38:24 Bilbo rtkit-daemon[2328]: Supervising 4 threads of 2 processes of 1 users.
Jul 28 16:38:24 Bilbo pulseaudio[13087]: [pulseaudio] pid.c: Daemon already running.
Jul 28 16:38:24 Bilbo rtkit-daemon[2328]: Successfully made thread 13090 of process 13090 (/usr/bin/pulseaudio) owned by '500' high priority at nice level -11.
Jul 28 16:38:24 Bilbo rtkit-daemon[2328]: Supervising 4 threads of 2 processes of 1 users.
Jul 28 16:38:24 Bilbo pulseaudio[13090]: [pulseaudio] pid.c: Daemon already running.
Jul 28 16:38:26 Bilbo mgaapplet[13108]: ### Program is starting ###
Jul 28 16:38:26 Bilbo net_applet[13107]: ### Program is starting ###
Jul 28 16:38:26 Bilbo hp-systray: hp-systray[13073]: warning: No hp: or hpfax: devices found in any installed CUPS queue. Exiting.
Jul 28 16:38:32 Bilbo mgaapplet[13108]: running: ionice -p 13108 -n7
Jul 28 16:40:30 Bilbo dbus-daemon[727]: dbus[727]: [system] Activating service name='org.kde.powerdevil.backlighthelper' (using servicehelper)
Jul 28 16:40:30 Bilbo dbus[727]: [system] Activating service name='org.kde.powerdevil.backlighthelper' (using servicehelper)
Jul 28 16:40:30 Bilbo dbus-daemon[727]: no kernel backlight interface found
Jul 28 16:40:30 Bilbo dbus-daemon[727]: dbus[727]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Jul 28 16:40:30 Bilbo dbus[727]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Jul 28 16:41:45 Bilbo dbus-daemon[727]: dbus[727]: [system] Activating service name='org.kde.powerdevil.backlighthelper' (using servicehelper)
Jul 28 16:41:45 Bilbo dbus[727]: [system] Activating service name='org.kde.powerdevil.backlighthelper' (using servicehelper)
Jul 28 16:41:45 Bilbo dbus-daemon[727]: no kernel backlight interface found
Jul 28 16:41:45 Bilbo dbus-daemon[727]: dbus[727]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Jul 28 16:41:45 Bilbo dbus[727]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Jul 28 16:43:00 Bilbo dbus-daemon[727]: dbus[727]: [system] Activating service name='org.kde.powerdevil.backlighthelper' (using servicehelper)
Jul 28 16:43:00 Bilbo dbus[727]: [system] Activating service name='org.kde.powerdevil.backlighthelper' (using servicehelper)
Jul 28 16:43:00 Bilbo dbus-daemon[727]: no kernel backlight interface found
Jul 28 16:43:00 Bilbo dbus-daemon[727]: dbus[727]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Jul 28 16:43:00 Bilbo dbus[727]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Jul 28 16:43:32 Bilbo mgaapplet[13108]: trying distributions list from https://releases.mageia.org/api/a/i586?product=Default&version=2&mgaonline_version=2.77.33
Jul 28 16:43:34 Bilbo mgaapplet[13108]: Computing new updates...
Jul 28 16:43:34 Bilbo mgaapplet[13108]: running: urpmi.update --update
Jul 28 16:43:36 Bilbo mgaapplet[13108]: updating inactive backport media Core Backports Testing (distrib9), Nonfree Backports Testing (distrib19), Tainted Backports Testing (distrib29)
Jul 28 16:43:36 Bilbo mgaapplet[13108]: running: urpmi.update Core Backports Testing (distrib9)
Jul 28 16:43:37 Bilbo mgaapplet[13108]: running: urpmi.update Nonfree Backports Testing (distrib19)
Jul 28 16:43:37 Bilbo mgaapplet[13108]: running: urpmi.update Tainted Backports Testing (distrib29)
Jul 28 16:43:39 Bilbo mgaapplet[13108]: Packages are up to date
Jul 28 16:44:13 Bilbo kernel: [250552.779895] nepomukindexer[13522]: segfault at 27fec ip b6cf9116 sp bfe68998 error 6 in libc-2.14.1.so[b6c83000+177000]
Jul 28 16:48:19 Bilbo kernel: [250798.815632] [drm] nouveau 0000:01:00.0: Setting dpms mode 1 on vga encoder (output 0)
Jul 28 16:49:03 Bilbo sensord: Chip: acpitz-virtual-0
Jul 28 16:49:03 Bilbo sensord: Adapter: Virtual device
Jul 28 16:49:03 Bilbo sensord: temp1: 21.8 C
Jul 28 16:53:00 Bilbo kernel: [251079.655696] [drm] nouveau 0000:01:00.0: Setting dpms mode 2 on vga encoder (output 0)
Jul 28 16:58:00 Bilbo kernel: [251379.656633] [drm] nouveau 0000:01:00.0: Setting dpms mode 3 on vga encoder (output 0)