Cuda 9.1 on Ubuntu 16.04 crashes X

I’ve been trying for a week now to install Cuda on my notebook with a GeForce GT 750M. It breaks my display in all possible manners. I followed the instructions from https://docs.nvidia.com/pdf/CUDA_Installation_Guide_Linux.pdf using the local .deb installer. The current situation is: Booting to the login screen works fine, but then, I’m stuck in a login loop. I managed to “solve” the login loop by adding “+iglx” to /usr/share/lightdm/lightdm.conf.d/50-xserver-command.conf as proposed in nvidia - Login Loop - "BadValue (integer parameter out of range for operation)" - 16.04 - Ask Ubuntu and restarting the lightdm service. Note that I still run into a login loop after booting unless I manually restart lightdm from a tty once.
Now, after logging in, I get to my desktop with the desktop icons but seemingly no unity, as there is no launcher, no window decorations, no menu bar etc.
Kernel version is 4.4.0-109. The output of the nvidia-bug-report.sh script is on Ubuntu Pastebin

Can someone please help me getting Cuda installed properly?

Laptops nowadays all use optimus technology, which involves both an intel iGPU and a NVIDIA dGPU, working together.

To fix the login loop, there are instructions in the linux install guide you linked. So one possible approach is to get the machine back to a state where the GUI is working (e.g. before you installed CUDA) and then follow those instructions.

So if you can get your GUI working normally, then clean out any old CUDA install (instructions are in the install guide) and then try the runfile install method with --no-opengl-libs switch.