If you blur everything out it makes it impossible to see whether something you've done might be causing the issue.
If it truly is a system glitch, and not an accidental layer you've overlaid or something, you may need an updated display driver. Visit the web site of the maker of your video card and download/install the latest display driver release for your OS and hardware.
Failing that, try going into Edit - Preferences - Performance, [Advanced Settings...] and changing the Drawing Mode. Make sure to close and restart Photoshop after making a change there and before testing.