kimac: Correct Firmware for iMac (CRTs) G3 233-700
Disclaimer: Apple does not necessarily endorse any suggestions, solutions, or third-party software products that may be mentioned in the topic below. Apple encourages you to first seek a solution at
Apple Support. The following links are provided as is, with no guarantee of the effectiveness or reliability of the information. Apple does not guarantee that these links will be maintained or functional at any given time. Use the information below at your own discretion.
Hello,
Before you update to OSX on any CRT iMacs you must be sure to update your Firmware to the correct one. In this post, I will tell you what update you will need, and if needed Firmware problem correctors. You must first know your model of iMac, look at this link or look at this, website to determine your model of iMac . For 333mhz and slower, 1.2 is needed. These are the iMacs with the tray loading CD room drive (where the optical drive allows you to insert the disk in a tray and push the tray in). For 350mhz and faster, 4.1.9 is needed. These are the iMacs with the Slot loading CD room drives (where you stick the CD/DVD room into a "slot" on the front panel of the computer). To check and see if your Firmware is correct you go to Apple system profiler – Production information – Boot Rom Version…
For 333mhz and slower, the Firmware will look like this if correct,
* Boot ROM 3.0.f3 - this is the 1.2 firmware update (corrections made on 4/15/05 thanks to a brody)
For 350mhz and faster, this is what it will look like,
*Boot ROM $0004.19F1 – 4.1.9
For slot loaders, you have to install Mac OS 9 or later first on your computer before installing firmware update 4.1.9.
For tray loading iMacs you need OS 8.5 at the minimum to install the Firmware version 1.2.
If you already got a Firmware problem black screen, no start up, start up for 5sec and shut down, you can still update the firmware after the fact by attaching a VGA display on any iMac DV or newer iMac model through the VGA port connector in back. Then doing the update. Or if you have the iMac 350mhz (the one with out the VGA ports) you can open up the computer shown in this link (thanks Kyle)
For 333mhz and slower and you have a Firmware problem black screen, no start up, start up for 5sec and shut down. you can fix it by unplugging the monitor witch is shown in this link pic three (thanks Djon) then connecting an external monitor and do the update. You can also check any of the of the links to fix the problem. This is also a great link to repair the Firmware problem and Giles - Fixing iMac(CRT) firmware/OS X problems . HTH
If the Firmware you are looking for is not shown look in this link.
Terry Holder -
<hr></hr>
with thanks to all contributors
Do you want to provide feedback on this User Contributed Tip or contribute your own? If you have achieved Level 2 status, visit the
User Tips Library Contributions forum for more information.