Screen saver not working / screen distorting

Hi John Wallace3,

Thanks for using Apple Support Communities! I see you're having an issue with the display on your iMac, and I'd like to do what I can to help.

Since it's just when the screen saver starts, if you change to a different one, does this continue?

How to display a screen saver on your Mac

If so, have you tried to reset the NVRAM? Reset NVRAM or PRAM on your Mac

If that doesn't resolve this, see if another user has the same issue: How to test an issue in another user account on your Mac

You can also give safe mode a try. Keep in mind, safe mode may make the screen flash and not look correctly.

Use safe mode to isolate issues with your Mac

If none of these steps resolve the issue, then you'd want to have your iMac looked at by a technician. You can use this link to find an Apple Store or Apple Authorized Service Provider and make a reservation. Find Locations

Take a look at this article before going in: Get your Mac ready for service

Take care!

Having a similar (same?) issue. Computer wakes itself from sleep with display as pictured. A mouse click restores the display to normal. Were you able to find a solution? Thanks!