[jlemons]

Ok, one of our tech specialists came to our school yesterday to help me out installing OS X on a few computers. Well, she forgot to upgrade the firmware. Now when the computer starts up the screen is black. It boots up as normal but there is just no monitor picture. This has happened to us before and I had to fix the problem. But, I have forgotten how to fix it. Does anyone here know the correct procedure for fixing this problem. There is something about putting it to sleep and waking it up again.

[proton]

What model Mac is this? If it's an iMac with an external video mirroring port you can plug an external monitor in and use that while you update the firmware.

- proton

[JKT]

Originally posted by jlemons:
Ok, one of our tech specialists came to our school yesterday to help me out installing OS X on a few computers. Well, she forgot to upgrade the firmware. Now when the computer starts up the screen is black. It boots up as normal but there is just no monitor picture. This has happened to us before and I had to fix the problem. But, I have forgotten how to fix it. Does anyone here know the correct procedure for fixing this problem. There is something about putting it to sleep and waking it up again.

Does zapping the PRAM not solve this? (hold down command-option-P-R at startup)

[jlemons]

It is an older iMac. No, zapping the Pram does not work. I found the fix last time on Apple Support page. It is something about putting the computer to sleep by pressing the power button and then there is another step that I forgot.

[JKT]

Originally posted by jlemons:
It is an older iMac. No, zapping the Pram does not work. I found the fix last time on Apple Support page. It is something about putting the computer to sleep by pressing the power button and then there is another step that I forgot.

Perhaps this hint at MacOS X Hints.com will help...

Edit: read all the responses below the article as well as there is more helpful info included there.