Now i think, that this problem is related to the graphic chipset / driver: I am able to switch to a tty blindly, log in there and execute command "sudo halt". So the system is still running, but the screen is "dead".
I cannot reproduce the issue if i run my system in "low graphic mode" (by introducing an error in /etc/X11/xorg.conf).
My systems graphic card: Intel GMA4500M
00:02.0 VGA compatible controller [0300]: Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller [8086:2a42] (rev 07)
Kernel driver in use: i915
Kernel modules: i915
Now i think, that this problem is related to the graphic chipset / driver: I am able to switch to a tty blindly, log in there and execute command "sudo halt". So the system is still running, but the screen is "dead".
I cannot reproduce the issue if i run my system in "low graphic mode" (by introducing an error in /etc/X11/ xorg.conf) .
My systems graphic card: Intel GMA4500M
00:02.0 VGA compatible controller [0300]: Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller [8086:2a42] (rev 07)
Kernel driver in use: i915
Kernel modules: i915