I just turned on my imac and was using it for a while . Suddenly the display got black out. Then I restarted my imac using power button and this weird display was showing stayed like this. What is this problem actually. How can it be recovered. Please help.
iMac 21.5″, OS X 10.11
Try to restart the iMac in Safe mode. If this is a problem with graphic driver software, that might resolve the issue. If it does, then you're lucky.
See if the problem continues to happen in Safe mode.
Restart your iMac and press and hold the shift-key when you hear the chime. Hold until you see the Apple logo and progress bar.
How to restart in Safe Mode…
Use safe mode to isolate issues - Apple Support
NOTE– starting up in Safe mode could take 5-10 minutes. Be patient.
Does the problem persist while in Safe mode?
Restart your Mac again normally and re-evaluate the issue.
I hope your Time Machine (or other) backup is up to date.
Try to restart the iMac in Safe mode. If this is a problem with graphic driver software, that might resolve the issue. If it does, then you're lucky.
See if the problem continues to happen in Safe mode.
Restart your iMac and press and hold the shift-key when you hear the chime. Hold until you see the Apple logo and progress bar.
How to restart in Safe Mode…
Use safe mode to isolate issues - Apple Support
NOTE– starting up in Safe mode could take 5-10 minutes. Be patient.
Does the problem persist while in Safe mode?
Restart your Mac again normally and re-evaluate the issue.
I hope your Time Machine (or other) backup is up to date.
Hello, Maniknratan.
That, my friend, is a definite sign of impending failure of the graphics system. Maybe the GPU... maybe a logic board issue. It may be a symptom of simply overheating. When was the last time you cleared out the cooling ducts?
If you're lucky the machine might come back to a normal display when it has cooled down. You did say you had been using it for a while when the display went black.
If the computer restarts normally after a bit, then you might try to download a copy of MacsFanControl to have a look at the temperatures that your computer is reaching as you use it. You can find the free utility here:
click > https://crystalidea.com/macs-fan-control
What model year iMac is this?
Which macOS version is running?
Thank you for your fast reply. The imac was off for whole day.. I was just turned on and using it only 10 minutes. Then it got black out. So there is no chance to get heated.
My imac is probably 2010 model.
Sudden weird display at startup
