Hi, Just wondering if anyone else with a 2013 Mac Pro has a similar experience - basically when I boot up my 2013 Mac Pro it just won't recognize connected monitors, I start up, hear the chime, the monitor backlighting comes on and then just goes off again - black screen. I usually have 3 monitors connected (2 Samsung 4K computer monitors via Displayport and 1 Samsung 4K TV) but in most instances I have to disconnect everything including USB and the other Thunderbolt ports apart from just one monitor cable and the power cable to eventually get it to work. Then I gradually reconnect everything and it usually works fine until I either have to restart or even when I switch off the monitors and switch them back on again, they are all black again until I go through the same procedure of disconnecting everything apart from just one monitor - very annoying, I am scared to switch my monitors off in case they all go dead and I can't get them back.