My monitor is fine...

I had a similar problem here: Windows 10 Upgrade: Black Screen During Installation/Reboot - Windows 10 Forums

Unfortunately it remains unresolved.

Care to elaborate? What do you mean by "I just stayed with it" ?

I tried upgrading to Windows 10 this evening, and during the installation process my computer rebooted a few times. The second time it rebooted, all I saw was a black screen and it stayed like that....