Bit of an odd one - upgraded to Mac OS Sierra, all working fine. When I shut the iMac down, the whole screen displays weird artefacts - (graphics glitch?), then shuts down fine. So not causing a problem, per se, but wondered if anyone else has had this issue?
iMac (Retina 5K, 27-inch, Late 2015), macOS Sierra (10.12)
hmmm,... well I updated about 2 months ago to 10.12.4 and had no artifacts on shutdown since except today again... a rectancle about a firestick size quite in the middle of the screen with all kinds of colors... appeard for about 3 seconds on shutdown... so definitively not fully fixed this issue.
Will go on observing...
Dominik Gschwind
Mostly yes using the macOS Sierra version 10.12.5. I say mostly yes as there is still a rare occasion when the artifact issue still happens. Maybe 2 out of 100 shutdowns. Prior to this OS update the issue happen 50% to 60% of the time so, it is much, much better...at least on my computer.
oh, I can confirm the same artifacts issue Charlotte!
I updated to 10.12.5 four days ago and it suddenly happened again... but the last 2 days were fine.
it would really be appropriate that someone from Apple would comment the issue in this forum!
It would for example be a good feeling to get to know that the issues don't have any influence on the imac's lifetime...
Having installed the 10.12.6 masOS Sierra it appears that the issue may have been resolved. I update phew OS a few days ago so will give it a bit more time before I feel it has even cured. I will say that Apple is very slow to respond (if and when they choose to respond) so they may have lost a lot of repeat customers. It would also seem to me that Apple does nothing to have their apps fixed either so... go figure. I guess they have so much market share they don't have to worry about fixing things that have been broken for a long time. (2017 - 2015 = 2 years)
And the other day for the first time in a while, "THERE BACK!" This happened a couple of days ago on shut down only once but it happened again it was the black 1/2 inch wide black line going from top to bottom horizontally across the screen moving down in a cascading fashion. It doesn't seem to hut anything other than it is once again an annoyance. Come on Apple guys get this fixed before my extended warrantee expires. (glad I bought it? Is that the and? you were looking for?
I have exactly the same problem, same model iMac. I had it picked up under warranty and they changed the logic board but it still has the same problem. I'm hoping it's a software problem which will be fixed when Sierra is updated.
This seems to be an on going issue that was resolved for a while. I am again working with Apple to try and figure out why this is happening again. It has gotten better and for awhile was gone. However, my iMac has started doing it again and I also get the spinning beach ball occasionally. These two issues don't seem to be related and the beachh ball may be cause by an app that I down loaded from the App Store. Don't know yet.
The artifact issue on my computer does not seem to cause an issue in performance. Apple did replace my iMac once after trying to fix the first one but so far Apple has not been able to pin point the cause. My own theory is the issue is cause by click throughs when surfing the web but then I am a novice at the Mac world so?... ?
Keep submitting feedback via this link and be hopeful for a fix!
http://www.apple.com/feedback/macosx.html
Some positive news here regarding the other graphics glitch being reported:
https://discussions.apple.com/thread/7714259?answerId=31271056022#31271056022
Don't think so yet: About the macOS Sierra 10.12.3 Update - Apple Support
However, I'm updating tonight and testing.
no issues on - macOS 10.12.2
no issues on
No problems for me yet in High Sierra. The graphical issue in the Time Machine also appears fixed.
The artefact/shutdown issue has been resolved in my case since Sierra 10.12.4 in late March. I didn't realize others were still having this problem.
I have all done clean installs via USB. Not sure if this has made a difference. Both the installer and the migration assistant completely failed on me for High Sierra, so ended up without another option anyway.
I have the same problem.
I wait for next update, than downgrade if isn't solved.
iMac 27" 5K Late 2015 screen artefacts on shutdown
