My Mint 17.3 system has a 950 and a 750ti installed. Nvidia driver 361.28. Everything works fine with a monitor plugged in. But if I run it headless, when I reattach a monitor it comes up with a black screen. I have had to restore the system twice now from backup because I couldn't get past the no display issue. It seems like something gets reconfigured when the system starts up with no monitor attached, but I have no clue what it might be. Any of you Linux experts have any ideas?