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Every time I logoff from Ubuntu 12.04 I get a black screen. If I logon again as if I could really see what I'm doing, the screen returns to normal. This doesn't happen with other two users on the same machine, with both of them I can logoff withouth problems. Any clues?

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What graphic card do you have? Did you updat the drivers? – Lucio Aug 4 '12 at 22:46
Thankx four your comment, Lucio. I have an integrated Intel GPU, just as rat2000 below. I will try his suggestion as soon as I can. – estebanknobl Aug 6 '12 at 14:31
So far, I have not been able to resolve this. Any suggestions? – estebanknobl Sep 21 '12 at 13:46

This is what I have done on my laptop. I have a integrated Intel GPU.

Force Pipe A Quirk

This problem typically exhibits itself on Intel graphics hardware (most particularly i855) by locking up the machine when closing the lid. The fix for this issue is to quirk your card to force enabling Pipe A. If you suspect you're having this bug, try setting this option in your xorg.conf:

Section "Device"
    Option "ForceEnablePipeA" "true"

Fore more reference visit the source of the above quote:

There are some possible fixes about ATI and nVidia.

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Rat2000: I use an Intel GPU as well. But my system doesn't use an xorg.conf file. Should I create one just for this or is there another way to force enabling Pipe A? – estebanknobl Aug 7 '12 at 0:54
Have you search in "/etc/X11/xorg.conf"??? do you use bumblebee??? I know you can make a xorg.conf file manually, but i don't really know how. – Rat2000 Aug 7 '12 at 2:30
Rat2000: there is no Xorg.conf file in that location, I think Ubuntu does not use that file anymore since 09.04, but indeed you can create one if needed. Thus, my question for a workaround. Thankx for your quick reply, I'll see what I can do. – estebanknobl Aug 7 '12 at 12:14
Any updates? I"ve been trying to use this quirk, but the instruction is very unclear. So do I just need to paste the above quote into my newly created xorg.conf? – Heisenberg Dec 8 '13 at 17:37
@Rat2000 I tried this on my ThinkPad X201i and my boot got stuck at Broke pipe: cannot write bytes. I had to boot into recovery mode and delete xorg.conf. – Heisenberg Dec 8 '13 at 19:42

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