gdm3 startup crash loop

[albert]

on Ubuntu 16.04, bumblebee testing and nvidia 3.75:

when choosing the nvidia gl driver from update-alternatives --config x86_64-linux-gnu_gl_conf, gdm gets stuck in a start-crash loop at startup, when choosing the mesa driver cuda applications do not work:

$ optirun ./simpleAssert
simpleAssert starting...
OS_System_Type.release = 4.4.0-83-generic
OS Info: <#106-Ubuntu SMP Mon Jun 26 17:54:43 UTC 2017>

CUDA error at ../../common/inc/helper_cuda.h:1133 code=30(cudaErrorUnknown) "cudaGetDeviceCount(&device_count)"

[albert (dr-moebius)]

see here:
https://github.com/Bumblebee-Project/Bumblebee/issues/888#issuecomment-313630826

cuda applications will compile, but not run (error code 999) when I configure the mesa driver with update-alternatives, see here:
https://github.com/JuliaGPU/CUDAdrv.jl/issues/50