1 iMac 21.5" Late 2012 slightly darker vertical stripe on screen
Hello fellow iFixers,
My iMac has this vertical area of slightly darker pixels, please see attached image. I’ve found a bunch of similar questions both here and on Google, but they all seem to be more severe cases than mine. It’s really barely noticeable, mostly on dark/contrast backgrounds, especially if I make the display very bright. It doesn’t seem to affect the image quality, it just… bothers me. I was planning to upgrade the RAM in this machine, and if there is a simple fix for this, I may as well go ahead with it. I know it’s a rather involved process, but since I was going to open it anyway… any suggestions greatly appreciated!
Update (08/11/2019)
Update: not sure if it's of any significance, but it doesn't show when I shared the screen on someone else's macbook. In addition, however crazy that may sound, it doesn't seem to affect any other desktop backgrounds (even dark ones), other than the two Mojave images (and their lock screens).
Update (08/12/2019)
I found an adapter and connected an external monitor. It shows no issue even with the same Mojave background, but the stripe is present on the built-in display.
Ist dies eine gute Frage?
1,1 Tsd. 
2,6 Tsd. 
5 Kommentare
Was the system opened before for service or upgrading?
What does an external monitor show?
von Dan
Can't say for sure as I'm not the first owner. I didn't even notice the issue when I bought it. I do have an external monitor I use with my PC laptop, but unfortunately, it doesn't have any compatible connectors.
von Mike Z
Update: not sure if it's of any significance, but it doesn't show when I shared the screen on someone else's macbook. In addition, however crazy that may sound, it doesn't seem to affect any other desktop backgrounds (even dark ones), other than the two Mojave images (and their lock screens).
(images didn't work in a comment, so I posted it as an answer below, now completely puzzled by this)
von Mike Z
That is expected as you are not using the GPU or the display of your system, you are using the other systems.
von Dan
Thanks Dan, that's what I thought. Just updated my post - there is no issue with an external monitor, suspect the built-in display might be damaged
von Mike Z