7 Replies Latest reply: Nov 15, 2012 8:54 AM by JimmK
fldharmabum Level 1 Level 1 (0 points)



I have the following machine:

Model Id:PowerMac11,2

Processor Name: PowerPc G5 (1.1)

Dual 2.3 GHz




Starting 12/28/2011 After I came home from work the Machine would not boot up. The white light would light up, the fans would start spinning normally but there would be no chime and nothing else would respond (keybord, monitor, etc). After a few seconds the fans will start spinning and getting louder. I forced quit it by holding down the power button. I tried to restarted and would get the same results.


I tried  the following:

Disconnected all devices/cables except keybord and monitor

Removed video card and put back in

reset the SMU

have not tried resetting PMU because the keybord was not getting power

removed all RAM

installed only 2 sticks of RAM


After doing all of the above to no avail, I put my ram back in (properly) and called it quits for the night. I unplugged the power cord from the back of the machine.


The next day after work I came home, plugged in the power cord and started the machine. To my surprise it bootted up just fine. I ran the utility tool to verify the disk and it failed (knowing that this is not the problem I decided to boot off the Installl disk and repair anyways). I hit restart and was back to the computer not responding and reacting like the night before (no response, then fans start reving). I tried to restart it a few times to no avail. Again I pulled the power cable out from the back of the machine and went to bed.


Today I came home and like the night before it started up, I booted of the CD this time and repaired the disk, re-verified and  all was well. I tried to restart it and i'm back to the machine not responding.


Any help with this is hugely appreciated!! Could it be the pram battery?


Please advice.



Thanks - Frank

Mac Pro, Mac OS X (10.5.8)
  • 1. Re: PowerMac G5 not starting properly
    BDAqua Level 10 Level 10 (116,475 points)

    Hi Frank,


    Certainly the cheapest thing to try...


    Might be time to replace the PRAM Battery, 4 years is close to their lifespan, far less if ever without AC power, & can cause strange startup problems...




    The other things that those symptoms remind me of is a bad Capacitor in the PSU needing to leak down, & heat related problems.

  • 2. Re: PowerMac G5 not starting properly
    fldharmabum Level 1 Level 1 (0 points)

    Thanks BDBqua for the reply. I changed the battery today and still nothing.


    I'm fresh out of ideas.


    Any help is hugelly appreciated.


    thanks- Frank

  • 3. Re: PowerMac G5 not starting properly
    BDAqua Level 10 Level 10 (116,475 points)

    Frank, my best guess is the Power Supply needs repair or replacing.


    One thought, is this plugged into a Universal Power Supply by any chance?

  • 4. Re: PowerMac G5 not starting properly
    fldharmabum Level 1 Level 1 (0 points)

    BDAqua, it's connected to APC which does need a new battery. The thing that I don't understand is why if I leave it unplugged for 24hrs or so it will start. However I tried this morning after replacing the battery and nothing. However the past two days after leaving if off all day (while at work) at night when I try it started (the first time but not if I restart or shut down and try to start again).


    just tried plugging it straight into the wall. Still, same results. No response, after a few seconds fans get louder....!!


    thanks- Frank

  • 5. Re: PowerMac G5 not starting properly
    kkita75 Level 1 Level 1 (0 points)

    Hi Could you please Clarify what solved your problem,I´ve been having this same problem on my G5 for ages and have tried all sorts suggestions which Ive read on different posts but no luck.


    My G5 will only click(and red light comes on for a second) once when I press power button but will not start...I´ve also tried switching on without the front Fan casing and a yellow light stays switched on on the board just by the power switch inside.


    If I take out the power cord and come back a day later or so my computer will start as if nothing is wrong with it,I have tried Apples Hardware tests and eveyrything seems fine.


    Please Help !





  • 6. Re: PowerMac G5 not starting properly
    fldharmabum Level 1 Level 1 (0 points)

    I'm sorry Danny but this post was accidentaly marked as answered when it really was not. I've yet to figure out a solution. I kept my machine on for months  until last friday when it crashed and was back to it's powering up issues. so i let it sit for 2 days and it came back up. i unplug the power chord from the back of the machine to let all the charge drain out. this at least lets me use it even if it is to a limited capacity.


    cheers - Frank

  • 7. Re: PowerMac G5 not starting properly
    JimmK Level 1 Level 1 (0 points)

    I just posted the same exact symptoms today. I was able to boot up (the next day, of course) from the G% install disk and hrad Apple Hardware Test. The thing listed logic board error post/192/0  I don't really know what the error is except post means "power on self test"