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I have a PC with ubuntu 12.04 which is connected to a video with a resolution of 1366x768, without mouse and keyboard. It happened that after some days of work , without any external input, but only showing a picture using the eog gnome picture visualizer, the video turn blank.

To restore the video activity it is not enought connect mouse and keyboard but I also have to connect a vga video.

The dmesg logger didn't provide usefull information

[   20.178175] drm: registered panic notifier
[   20.179002] [drm] Initialized i915 1.6.0 20080730 for 0000:00:02.0 on minor 0
[   20.179105] snd_hda_intel 0000:00:1b.0: PCI INT A -> GSI 16 (level, low) -> IRQ 16
[   20.179235] snd_hda_intel 0000:00:1b.0: irq 49 for MSI/MSI-X
[   20.179296] snd_hda_intel 0000:00:1b.0: setting latency timer to 64
[   20.245573] ADDRCONF(NETDEV_UP): wlan1: link is not ready
[   20.252944] ADDRCONF(NETDEV_UP): wlan1: link is not ready

[   20.308345] hda_codec: ALC888: BIOS auto-probing.
[   20.329377] input: HDA Intel Mic as /devices/pci0000:00/0000:00:1b.0/sound/card0/input4
[   20.343356] input: HDA Intel Line-Out as /devices/pci0000:00/0000:00:1b.0/sound/card0/input5
[   20.922147] type=1400 audit(1371021068.328:7): apparmor="STATUS" operation="profile_load" name="/usr/lib/lightdm/lightdm/lightdm-guest-session-wrapper" pid=877 comm="apparmor_parser"
[   20.928181] type=1400 audit(1371021068.336:8): apparmor="STATUS" operation="profile_replace" name="/sbin/dhclient" pid=878 comm="apparmor_parser"
[   20.933862] type=1400 audit(1371021068.340:9): apparmor="STATUS" operation="profile_replace" name="/usr/lib/NetworkManager/nm-dhcp-client.action" pid=878 comm="apparmor_parser"
[   20.934742] type=1400 audit(1371021068.340:10): apparmor="STATUS" operation="profile_replace" name="/usr/lib/connman/scripts/dhclient-script" pid=878 comm="apparmor_parser"
[   21.000854] type=1400 audit(1371021068.408:11): apparmor="STATUS" operation="profile_load" name="/usr/lib/telepathy/mission-control-5" pid=884 comm="apparmor_parser"
[   22.525335] [drm] Changing LVDS panel from (+hsync, +vsync) to (-hsync, -vsync)
[   50.744140] usb 3-1: USB disconnect, device number 2
[   51.984144] usb 3-2: USB disconnect, device number 3

After 2 o 3 days of working the screen will be blanked bu not messages were reported in dmseg. Inside the log file dmesg is starting to receive new messages only today, 5 days later, after I connected the keyboard, the mouse and a vga screen.

[435855.408093] usb 4-1: new low-speed USB device number 2 using uhci_hcd
[435855.657348] input: Dell Dell USB Keyboard as /devices/pci0000:00/0000:00:1d.2/usb4/4-1/4-1:1.0/input/input6
[435855.657924] generic-usb 0003:413C:2003.0003: input,hidraw0: USB HID v1.10 Keyboard [Dell Dell USB Keyboard] on usb-0000:00:1d.2-1/input0
[435961.228113] usb 2-1: new low-speed USB device number 2 using uhci_hcd
[435961.399319] input: HID 062a:0000 as /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1:1.0/input/input7
[435961.399868] generic-usb 0003:062A:0000.0004: input,hidraw1: USB HID v1.10 Mouse [HID 062a:0000] on usb-0000:00:1d.0-1/input0

Any suggestion on what to check to analize this strange behaviour ?

Regards, Enzo

share|improve this question
what's in dmesg | tail ? – modosansreves Jun 17 '13 at 8:57
P.S. is probably a better stackexchange site to ask the question – modosansreves Jun 17 '13 at 8:57
I add the output of dmesg in the main section of this post, but I think theren't been usefulle info. – enzo2 Jun 17 '13 at 12:05

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