iMac 27 2011 Black screen, no power beep, fans spin, cd drive sound
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
Is this a good question?