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Hi all,
I’ve had my iMac for around 5 years and have had no issues.
Today when I turned it on, all I’m getting is coloured blocks across the screen.
After about a minute of displaying this, it restarts by itself and does the same thing.
Any ideas?
Thanks!
Not good, it appears to be a failed GPU. You can try restarting in Safe Mode however I think your next step after doing that is making an appointment at your local Apple Authorized Service Provider to have it professionally diagnosed. Below are Safe Mode restart instructions:
Please restart the computer in Safe Mode per the directions in the How to use safe mode on your Mac - Apple Support link.
Note: If you are using a wireless keyboard please either plug it in using the supplied Lightning cable that shipped with it. If you are using a legacy keyboard or a third-party keyboard that does not have re-charging abilities, please use any USB keyboard. Also note that a Safe Mode restart may require you to hold down the shift key for up to 5 minutes before the computer starts in Safe Mode. You will know it is in Safe Mode when you see “Safe Mode” in the upper right of the display.
Not good, it appears to be a failed GPU. You can try restarting in Safe Mode however I think your next step after doing that is making an appointment at your local Apple Authorized Service Provider to have it professionally diagnosed. Below are Safe Mode restart instructions:
Please restart the computer in Safe Mode per the directions in the How to use safe mode on your Mac - Apple Support link.
Note: If you are using a wireless keyboard please either plug it in using the supplied Lightning cable that shipped with it. If you are using a legacy keyboard or a third-party keyboard that does not have re-charging abilities, please use any USB keyboard. Also note that a Safe Mode restart may require you to hold down the shift key for up to 5 minutes before the computer starts in Safe Mode. You will know it is in Safe Mode when you see “Safe Mode” in the upper right of the display.
Coloured blocks across iMac screen when turning on
