Partial black screen at Windows startup

[panz3r88]

Hello, I am trying to figure out a problem that arised on all the PC of the machines we are selling after we updated them from Windows 7 to Windows 10.
Sometimes it happens that after the machine is turned on, the login screen appear like in the image I attached: only the top left part is visible and the rest of the screen is black.
If I move the mouse pointer on the black part of the screen I can see it and do operations(if there is an icon in that part of the screen I can click on it for example).
If I press Windows+P or WINDOWS+CTRL+SHIFT+B I can see again the full screen, but the problem can arise at a new startup of the machine.
The problem can also appear again by doing login and logoff various times.
Since I saw the problem on machine with different hardware(for example some have a Radeon RX 480, others a GTX 1060) and with different monitor maybe the problem is in some OS settings, or in how the clones used to create the other hard disk have been created? At the moment I have no clue and I am trying to find something that removes completely this problem, but I did not find someone with a similar problem

 

[Garyw]

Try running sfc /scannow from an elevated command prompt. If the first time reports no errors, run it again. In any event, post back with results. {Right click on the start menu to get this}.

 

[panz3r88]

I tried to do it but I did not get meaningfull messages I think.
But I did it again a couple of times like you suggested and you can see the result of both files I attached

 

[Garyw]

The message says that SFC didn't find any broken systen files (good news). Try right clicking on a blank area of the visible background. Click on Display settings.

You should see this:

See if the resolution says (Recommended). If not, scroll the list to see if another setting is recommended.

You mention different graphics cards, but it's possible that when you upgraded, M. S. installed generic drivers. Check the computer mfg. website (preferred) or card mfg. website for the correct drivers and install.

Please post back with the results.

 

[davehc]

A thought.
You could be configured wrongly in multi tasking?
Settings .System - Multitasking. Or a connection to a wireless display.
By default, both items should be saying "Only the Desktop I am using."

The suggestions comes to mind from your reference to the Windows -P action.

This would normally bring you to this: