Created attachment 443748 [details] emerge --info When turning off the monitor for longer periods of time, a few minutes won't do, but a few hours will, there will be no video from X.org. Switching to a framebuffer console will bring perfect video, however switching back to X.org will not get you any video signal any more. Temporarily unplugging the monitor does not change the situation. The graphics chipset is the integrated graphics of the "Intel(R) Core(TM) i7-5557U CPU @ 3.10GHz".
Created attachment 443750 [details] xorg log of such a failed session
Maybe this is an important point, but when you switch to a framebuffer console before turning off your monitor, it'll work just fine.
1. what DE are you using 2. please try "echo xterm > ~/.xinitrc && startx"
I'm using Xfce. When starting the X-server purely as suggested it seems to work fine.
