HT201177: Get help with video issues on external displays connected to your Mac

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Inexco

Q: IMac screen goes black and will not return without power cycle.  Time of events 19 min to 43 seconds after desktop shows

Display goes black

19 min is longest it lasts goes down to 43 seconds after desktop appears

 

Just updated to Mt Lion same time this started

 

I am guessing video card went out at same time?

 

Do not have D test for hardware after upgrade.

 

20 inch 2.4 Core 2 duo 2gig. Ati radon hd 2600 256 mb graphics

 

Suggestions?

iMac, OS X Mountain Lion

Posted on Jul 27, 2012 8:47 AM