Black box appears in the corner of the screen during most games, especially on desktop computers.
Black box appears in the corner of the screen during most games, especially on desktop computers.
The black box appears in-game but disappears on your desktop, occurring across most titles.
Have you attempted to power it off and on again? Laughing at the joke, but when did this begin? Which part of the screen is it? If it's the lower right corner, did you install any new software near the program menus besides the sound control, etc.? By the way, I'm assuming you're using Windows 10.
I suspect a menu issue is causing problems in fullscreen mode. I'll attempt to open and close the context menus, covering all options like the calendar, and see if the black square remains.
It might be an overlay running in the background. Do you have anything similar available?