Another possible fix for dead-screen G3 iMacs

Feb 24, '05 08:07:00AM

Contributed by: poenn

I think that most of you know the situation: You want to install OS X on an old iMac G3. If you don't update its firmware before the installation, your iMac won't display anything on the screen any more. I had this issue in the past when I didn't know about that requirement. On some models, you get at least a very(!) dark screen, but most will just stay completeley black. Once I even had one which was dark pink. In the past, I used different tricks to revive the dead iMac:

All of the above just to get to the point of running the Firmware Updater. After the update, the iMac still starts with a blank screen. However, after turning it off and on again, it finally works, and you can begin to install OS X. The biggest annoyance is that after you've booted once with the Installer CD, it's already too late. If you have an older firmware, the installer will not be able to continue at the point where you select the destination drive, and after a reboot, your screen is dead.

Not having installed OS X on such an ancient machine for a long time, I forgot about the firmware update requirement, and booted off the OS X Installer CD. I think you can guess what happened then. Firmware too old, no screen. So I went through the steps above and at the point of creating a bootable system with a VNC Server on it (like I have done succesfully in the past), I learned something even easier.

Start up the screen-dead iMac, let it boot into OS 9, and wait until the Finder has loaded -- you can guess that pretty well by the sound of the HD. Then push the On/Off button to put the iMac to sleep. When the green LED turns to a blinking orange, your iMac is asleep. Then wake it up with a keystroke on your keyboard and (presto!) you have your screen back!

Be aware that the display only will work until your next reboot/shutdown, so now would be a good time to run the Firmware Updater! After the update, the iMac will boot once more with a dead screen (as stated above), but after another shutdown, it will be alive again from then on. You can install OS X without any problems now. I know that the problem should be well known, but I haven't seen this simple solution anywhere on the net, so I decided to share my experience.

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