I'm running AKiTiO + Zotac GTX970 + MBP15 late 13 setup on windows 7 in mbr mode and it's fine. But now im trying to move all of these on window 10, temporary testing on USB external HDD for exeriments. So, what im doing. I'm starting fresh windows 10, install bootcamp, shutdown, connect eGPU, startup, install nvidia drivers, restart. After that moment windows wont startup - the white dots cycling around infinitely and hdd keeps silence. I tried: install windows in MBR and EFI mode, use old bootcamp drivers and new bootcamp drivers, update windows fully and not update windows at all, install latest nvidia drivers and 361, update intel iris drivers. All the same, it just hangs on startup if eGPU is connected. Once i managed to load at last. Device manager reported everything is ok, but optimus mode was not working at all. I could not boot window anymore.
I read the posts in thread about nvidia released windows 10 optimus support, and nobody seems clushes with such problem as me.