I understand you are connecting 3 monitors via Display port MTS and every time you reboot, looses one of the monitors. Based on the display port information I got from engineering department, that's the way 3 monitor configuration will work for Intel HD Graphics 5000.
See the following URL for additional information:
When the bandwidth/dot clock exceeds the maximum allowable limits, a monitor might not show up in the Intel graphics user interface. The graphics driver dynamically enumerates displays in the Intel® HD Graphics Control Panel/Graphics and Media Control Panel based on the bandwidth availability.
Thanks for the reply. I'm not sure this is a case of exceeding maximum bandwidth. (3 x 1080p is far less bandwidth compared to DisplayPort 1.2 maximum). The monitor actually shows up on the control panel as being active, so it is being detected, but not driven. I can disable and re-enable the monitor and then all is well. If I can correct the problem after boot, then surely there is a way for this to work automatically after reboot. Interestingly when I configure the 3 displays as a collage as opposed to extended desktop, most of the time they all come up fine. Surely someone else has run into this issue. I can reproduce this on 3 of my Intel NUC's. Appreciate any support here.