Tried with kernel 4.7.2. The problem continues. 

I have switched around, and the HDMI works with the screen, though only 60hz. 
The screen is on at post, but dissapears during ubuntu startup, after grub the
screen remains dark. 

DRM 2.45.0 / 4.7.2-040702-generic, LLVM 4.0.0

kind regards B.