Resolved 2009 24" iMac Odd Display Issue

[MacForScience]

Any thoughts?

My guess is a beginning to fail LCD panel. I really hope not.

What I Have Tried

• 
  Rebooting (no change)
  Changing Users (no change)
  Changing Resolution (no change)
  Taking a screenshot to see if it is GPU or LCD (definitely LCD)
  Plugging in an external monitor (issue is not present on external monitor)
  Ran Apple Hardware Test 3 times no issues

Guesses? Suggestions?

Thanks!

 

[minimalism]

Any thoughts?
Image

My guess is a beginning to fail LCD panel. I really hope not.

What I Have Tried

• 
  Rebooting (no change)
  Changing Users (no change)
  Changing Resolution (no change)
  Taking a screenshot to see if it is GPU or LCD (definitely LCD)
  Plugging in an external monitor (issue is not present on external monitor)
  Ran Apple Hardware Test 3 times no issues

Guesses? Suggestions?

Thanks!

I'm guessing these are smudges inside the LCD.

 

[MacForScience]

I thought about that, but I have never taken the front glass off. How would it get smudges inside?


Thanks

 

[MacForScience]

The issue seems to have resolved itself. Not sure why.