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I have an HP Elitebook laptop with a docking station. The docking station has two dual-mode DisplayPort ports, and I have a monitor hooked to both. In Windows, I can get both monitors working independently. But in Ubuntu, they always have mirrored displays and only one is detected.

My graphics card is listed as Intel® Haswell Mobile

Here's the paste from xrandr --verbose

Here's my monitors.xml and here my sudo lshw

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  • Could you also post monitors.xml to paste.ubuntu.com?
    – Fabby
    Oct 7, 2015 at 23:47
  • Oh, you should have dropped me a comment back in October... Can you do a sudo lshw too and post that to paste.ubuntu.com as well (and the hardware config from Windows would be nice as well) After that, leave a comment @Fabby! ;-)
    – Fabby
    Dec 20, 2015 at 0:27
  • @Fabby Here's the output from sudo lshw
    – Ron Romero
    Dec 24, 2015 at 0:24
  • Thank you! Favour returned! Question upvoted!
    – Fabby
    Oct 9, 2018 at 11:26

2 Answers 2

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+50

If your displays are identical, please:

  1. Make a back-up of your current monitors.xml:

    cp ~/.config/monitors.xml ~/.config/monitors.bak
    
  2. Download the following monitors.xml and overwrite yours.

  3. Log off and log on again! (If that doesn't help: reboot)
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  • Is this file under root or user account? Either way I don't have it on my Ubuntu 16.04 desktop setup. What's the fix in this case?
    – Dimon Buzz
    Oct 12, 2017 at 16:53
  • This was a very specific answer to a very specific question and doesn't apply in your case. Please ask a new question
    – Fabby
    Oct 13, 2017 at 7:56
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The "DP2 disconnected" message point to deeper problem..

  1. and after a short search I have to say, that most probably it is a bug: https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-intel/+bug/1104230

    If this is your case, you can monitor the issue and use daily kernel build after the issue is fixed and use solution #3 bellow until the issue is fixed.

  2. Another reason could be, that monitor on DP2 is not sending correct EDID info. Try to diagnose this by swapping the monitors physically. After that it should say "DP1 disconnected".

    If this helps, let us know, and you can probably succeed with xrandr --addmode commands. but be ready to weird behaviour after you undock the computer, because things will not go automatically and you should always switch display off before you undock/unplug.

  3. Another solution for you could be to simply use another output RGB, DVI or HDMI as the second monitor, depend on what is available on your docking station.

    Understand that this is not a solution you are serching for, but most probably will work even after the issue #1 is fixed.

There is some helpless discussion on Intel pages with an Intel staff on that issue, but without any conclusion: https://communities.intel.com/thread/51364?start=0&tstart=0

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