I too have a similar situation. Upon power up, I see the choice to go into safemode, then the screen goes black, with the cursor. If I wait about 5 minutes, the computer boots up and I can use it. This happens about half the time. I notice that when I get to Windows, the Avast Premium Cleanup is on the screen, having "Fixed the Problems", that I fixed a week ago.
I have tried looking for some kind of setting where I can get Premium Cleanup to NOT do it's automatic thing, but can't find a scheduler or task program.
The black screen issue has been happening much before the Premium Cleanup is automatically cleaning the same thing this last week.
Any helpers out there?
Windows 10