Hi,
I have a Lenovo X1 Carbon (2nd generation) with Intel HD Graphics 4400, connected to two Dell U2713HM monitors via EVGA DisplayPort MST hub. About half of the time it works correctly, but other times when I plug in the DisplayPort cable to the laptop, one of 3 things can happen:
1) all the monitors display some picture, then go blank, then display something again, then go blank, ad infinitum
2) one or two of the monitors are blank, and if I go to Windows Screen Resolution window, I can manually select "Extend desktop to this display", and all the monitors then work as expected
3) like (2), but one of the monitors shows only 1920x1080 as the maximum resolution (the correct resolution is 2560x1440)
Sometimes the endless loop also happens out of the blue (when I'm not connecting any cables, just during normal work). Also, sometimes the displays just go black for a moment and then resume working normally.
I contacted EVGA support, and they told me it must be a graphics adapter/driver issue.
I have Windows 8.1 x64 with the latest Intel Graphics Drivers (15.36.3.64.3907, driver version 10.18.10.3907). I've also installed the latest BIOS from Lenovo (1.17/GRET40WW).
Thanks,
Magnus