HP Z440 PC with two monitors connected (DVI and displayPort)
Usually everything works fine. But sometimes, when I power on, both of my screens goes dark. This happens right after the HP logo appears. Waiting does no difference, and restart makes it only enter the same state again.
To solve this, I need to unplug second monitor (display port). Then start system.
After a bootup, I can then replug my monitor and everything works fine.