9 Replies Latest reply: Jan 7, 2012 3:56 PM by noondaywitch
Matt Mathison Level 1 Level 1

Hi all, I just wanted to post some success I just had with a mid 2007 20" Aluminimum iMac having a strange error where on bootup had "3 short, 3 long, 3 short" beeps.


Now after ringing Apple Support and my local Apple repairer and being told that the logic board had failed and needed replacing, I just could not accept that. I opened my mac and discovered (using the 4 LED lights on the logic board) found that the logic board was fine, just the firmware had somehow got corrupted and the computer was freaking out.


What I did to remedy this was to download the correct firmware restoration CD off the Apple Support Website and restore the firmware.


5 mins later VOILA!!!!! Machine was booting again and chugging along nicely.




I just saved myself $1000 by trying this first. Im amazed that I was told by Apple themselves that my logic board needed replacing and they didnt even suggest that I should try a firmware recovery first.

  • baltwo Level 9 Level 9

    Thanks for the feedback. I suggest filing a report with Apple via http://www.apple.com/feedback/macosx.html

  • HarryStep Level 1 Level 1

    Hey Matt,


    I'm having similar issues with an early 2008 24" iMac. I get two sets of beeps depending on the type of ram installed. With the old Samsung ram I get three beeps, a pause, three beeps and so on (apparently indicates ram did not pass integrity test/no good banks). I ordered new Crucial ram and on start up it beeps once, pause, another beep (indicates no ram installed).


    So, my question to you is, how were you able to restore the firmware when your computer was beeping? Did you have access to the OS somehow? My computer gets stuck at the beeps and is unable to do anything else.


    Thanks for your help.

  • Matt Mathison Level 1 Level 1

    Hi there, it seems that you may have a faulty RAM slot by the sounds of it. If you have another iMac somewhere maybe try to borrow the RAM out of it temporaily to do some testing. It would be unlikely that two sticks are faulty but I have come across it before.


    I was lucky with mine, I would say that software update had a failed attempt at doing a firmware update and it crashed my logic board. How I got to recovery wa by following these stpes:


    1. Find a spare Apple laptop or desktop and head over to the apple support website and download the correct firmware for your iMac. THIS IS IMPORTANT TO GRAB THE CORRECT SOFTWARE AS IF YOU GET THE WRONG ONE YOUR IMAC MAY BE DAMAGED. Once you have done this follow the instuctions on the website to burn the firmware to a cd


    2. Unlpug all cables including power cable from your iMac and hold the power button down.


    3. Keep holding the power button down and reconnect the power cable. Once connected release and press and hold the power button until you hear one long beep


    4. Do not let go until you hear this very long beep as this indicates you are in firmware recovery mode


    5. Once you have heard the long beep let the power button go and then insert the cd that you have just burnt


    6. Let the iMac read the disk and it will show a grey screen with a status bar indicating that it is installing the firmware.


    7. Wait for the process to finish and let the iMac reboot.



    If all has gone well that should revive your imac and you should be right to go. As I mentioned before if you can try another stick of RAM first you may just have two faulty ones. If you have tried or cant get another stick and its still playing up, then I would say that your logic board definately needs replacing.


    Let me know how you go

  • HarryStep Level 1 Level 1

    Hey again (thanks for replying),


    So it seems as if the EFI firmware update is out of the question. The model identifier for my iMac is 8,1, and for whatever reason, Apple has not released/skipped a firmware download for that specific model.


    See this page: http://support.apple.com/kb/HT1237


    The firmware for the iMac models range from 4,1 to 12,2, with only 8,1 missing, which seems rather odd.


    If you can find it somewhere else, let me know.


    I managed to install an old copy of Leopard on the machine (10.5.4). Doing that should roll back the fimware right?


    Right now I have 4 dimms in total (2 OEM Samsung, 2 new Crucial). The new Crucial dimms bring up the one beep error, while only one of the old Samsung dimms leads to the three beep error. But get this, the other old Samsung ram works wonderfully and has passed a series of tests with flying colors...in both slots! I've run the extended AHT three times and there are no issues. I have also run Memtest in single user mode which passes all tests. Also ran the hardware test suite in TechTool Deluxe, again passing all tests.


    I really don't think both of the brand new Crucial dimms I bought are bunk. For whatever reason, the one old Samsung dimm seems to be working.


    Let me your thoughts, suggestions...

  • noondaywitch Level 6 Level 6

    RAM problems with new modules usually mean you haven't seated the RAM properly. They do require a very firm push to engage.

  • HarryStep Level 1 Level 1

    If I were to push with any more force, I'd probably break something.

  • noondaywitch Level 6 Level 6

    That sounds about the required amount. Do you feel a soft click when they seat?


    We can assume from your trial that one of the Samsung cards is bad.


    I'd be surprised if the Crucial ones are, especially both, but it may be worth calling them and getting an opinion. They'll usually exchange RAM if there's a doubt about it.


    I'm assuming, of course, that new RAM is the same specification as the original, i.e. PC2 6400 DDR2 SDRAM 800MHz.

  • HarryStep Level 1 Level 1

    Thanks for the suggestion about the soft click!


    I've got it up and running with the 2 Crucial dimms now.

  • noondaywitch Level 6 Level 6