2 iMac 27 2011 Black screen, no power beep, fans spin, cd drive sound
Hi all,
After trying a lot of things I'm a bit clueless.
I got a iMac 27" mid 2011. I started having blue/green stripes. So I guessed the GPU was bad and needed to be replaced. Before the new GPU came in it was already dead: black screen
I ordered a ATI Radeon HD5750 to fix the problem. After installing I still had a black screen.
- LED 1 - On
- LED 2 - On
- LED 3 - Off
- LED 4 - Off
Tried PRAM/SMC resets.
After a while I didn't get any power beeps any more. So I tried another motherboard but still no power beep.
It turns on with black screen, fans spinning and optical drive making noise. After a while the fans go full speed.
- LCD is working fine on other iMac.
- Got no external video output.
All help would appreciated
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4 Comments
I think you have a bad GPU board. Where did you get it? You need to have one that has the Apple firmware.
by Dan
Ebay. Listed as working from mid 2010 model
by Szal
Put your original GPU back in to see if the blue/green stripes reappear (good sign!) If not you have deeper issues than the GPU board to fix.
by Dan
i tried the gpu in a 2010 model and it is working...
next to gpu, logic board, lcd and powersupply working what could it be?
by Szal