That's an old problem that I've got here, I'm trying to use my CPU Intel for display (nvidia prime). The problem is that after switching in the setting to Intel, my OS won't boot or login if I unlogged. That's a black screen. I'm using the recommanded driver for my CPU and the Nvidia's Driver purpose by ubuntu (v 384). Is it a problem with the nouveau driver or a compatibility with my hardware ? I've got a I5 7700 and a gtx 1050. Can anyone know how can i use my Intel CPU for the display ?