yesterday I just updated Ubuntu Gnome from 15.10 to 16.04. I have an external monitor connected to my Asus G55VW notebook via HDMI. After the update there weren't any problems until today, when I brought out my notebook from my room (unplugged HDMI). When I turned it on and after selecting "Ubuntu" on the Grub screen, the notebooks screen starts to flicker and nothing happens.
After a few trying I brought it back to my room, connected to my external monitor and the system booted up. I turned off the second screen in the Display menu, but it didn't help. I changed the nvidia driver back to version 340 from 36x, but it didn't help neither.
So at this moment I can only use my notebook with an external monitor. Interesting is, that when the screen flickers and I connect it to the monitor, the system boots up automatically, without restarting.
Notebook config: CPU: Intel Core i7-3610QM GPU: nvidia 660M GTX, RAM: 8GB SSD: SanDisk U100 128GB
Does anyone here have a possible solution for this? I already opened a ticket here: https://bugs.launchpad.net/ubuntu-gnome/+bug/1574060 maybe its an nvidia bug or something, but maybe here someone will help me out too.