Display Port monitor not detected Ubuntu 14.04 - VGA ok - Intel GC

Solution 1:

I found a possible solution to my problem.

I just went here: https://wiki.ubuntu.com/Kernel/LTSEnablementStack#Ubuntu_14.04_LTS_-_Trusty_Tahr

And followed the instructions to do the Ubuntu LTS enablement (also called HWE or Hardware Enablement) stack.

For Ubuntu 14.04 (my version) I just did

 sudo apt-get install --install-recommends linux-generic-lts-xenial xserver-xorg-core-lts-xenial xserver-xorg-lts-xenial xserver-xorg-video-all-lts-xenial xserver-xorg-input-all-lts-xenial libwayland-egl1-mesa-lts-xenial

For Ubuntu 16.04 you should do

sudo apt-get install --install-recommends linux-generic-hwe-16.04 xserver-xorg-hwe-16.04 

I just did that command, rebooted and the monitor were detected without any problem. This is my highly suggested solution. Read more about it on the link above.

I hope this will help someone else with the same problem

Solution 2:

The problem here is the Intel display driver. If you are willing to take the risk you should uninstall the Intel display driver. The system will fall back to a modesetting generic driver. Your monitors will now work but graphics quality will be worse.