Black screen after installing nvidia drivers ubuntu 15.10 x64

My Laptop Asus F555LB with CPU i5 and nvidia 940m
with this driver I have always problems.
after installing :
nvidia-XXX nvidia-settings nvidia-prime
XXX - 352 358
after reboot I get a BLACK SCREEN.
And I can not do anything. I am forced to reinstall Linux.
I am very angry and no one will recommend the products of your company

How did you install the driver. I’d also bet that switching to a differen TTY or booting with nomodeset would still have worked to fix the problem from there.

You actually does not have reinstall everything, use chroot from live media… At least you can get logs from failed boot from there. The reason for black screen might be as simple as some kms modeset(intel maybe) driver is interfering nvidia_modeset driver. So you should try to use nomodeset boot parameter for kernel(press down shift while you boot to get grub menu and press e to modify boot entry. Then use arrow keys and add nomodeset to the end of line linux /boot/vmlinu… ro quiet splash or similar).

But your actual problem is optimus, you are now trying to use prime with xrandr offloading(I don’t have idea how well ubuntu has packaged nvidia drivers, that is it even actually working). If you can’t get it working you can try to use bumblebee instead:
https://wiki.ubuntu.com/Bumblebee#Installation