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HELP WITH IMAC G5 4,1 POWERING ISSUE
Posted by: ROLLERMANZ on 2014-11-13 10:10:34
Hello Guys,

I have an IMAC G5 4,1 which has a 2.0GHz Intel Core Duo Processor, 2GB RAM, 250 HD and is iSight. 

I recently thought about upgrading its processor to Intel core 2 Duo so i ordered a processor online and got it yesterday. I took the IMAC apart and replaced the processor, The processor fitted well in and was made for it's processor socket on the logic board. I turned the IMAC G5 on and it turned on for a sec and then turned off.. I therefore knew that this is surely not going to work so I put the original processor back in and turned it on and the computer on but there was burning smell coming out of the IMAC, I took the screen off and then restarted and saw that one of the fan was not turning on and because of that the other 2 fans were really spinning like a vacuum cleaner. anyways I fixed that as well and now all  3 fans are spinning at their normal speed. 

THE ISSUE NOW IS that whenever I turn the IMAC G5 on, it turns on for like 4 seconds and then turns off automatically, I've been researching online and found about SMU reset, PRAM reset, DID ALL OF THAT BUT STILL NOT SOLVED.. the IMAC maybe once in an hour turn on and boots well but then after some time the processor FAN ONLY starts to go so loud and then it turns off.. all the fans r really clean so i don't think it can even get overheat like this because of dust.. there is no dust..

THE IMAC HAS ALL ITS MANUFACTURE COMPONENTS IN IT, IT TURNS ON FOR 5 SECONDS AND THEN CUTS OFF WHILE YOU HEAR THE CHIME AND ITS OFF AUTOMATICALLY.. THERE IS NO DUST/SMOKE OR ANY KIND OF SMELL COMING FROM THE COMPUTER NOW.. IF BY ANY CHANCE IT BOOTS INTO THE OS X THEN THE FAN WILL GET RALLY HEATED UP AND SHUT DOWN THEN ASWELL.... 

Is this something to do with the power supply, I took the power supply out and had a look at it, I can only see two capacitors that have A bit of fluid on thEIR joints but no capacitor is swollen or anything... PLEASE PLEASE PLEASE DO HELP AS ITS REALLY FRUSTRATING NOW, I ONLY GOT THIS A WEEK AGO AND ITS ALREADY ON THE DEATH BED.. PLEASE HELP... SEE THE ATTACHED IMAGES FOR A CLEAR VISION OF WHAT I AM TRYING TO SAY.. THANKS ALOT GUYS.. 

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Posted by: TheWhiteFalcon on 2014-11-13 10:20:01
Pretty sure you have to update the firmware before you upgrade the CPU.

Also, that's not an iMac G5 if it doesn't have a PPC processor. It's just an Intel iMac.
Posted by: Macdrone on 2014-11-13 11:29:56
Power supplies are suspect in the Intels. I have one I bought at goodwill and replaced with another power supply. Been working well ever since.
Posted by: Macdrone on 2014-11-13 11:32:02
And yes it was burnt, and burnt bad. I think the G5 iMacs have the same power supply. I say that as I think it's beefed up for the G5 and would do well in the Intel.
Posted by: ROLLERMANZ on 2014-11-13 12:11:00
So what should i do now ?? buy a new power supply which is around £30 pounds .. ?
Posted by: Macdrone on 2014-11-13 22:32:14
If you want to save it, or rebuild the one you have. I was lucky I had a lines screen imac G5 and just moved the power supply over.
Posted by: ROLLERMANZ on 2014-11-14 06:39:41
Is there no way to repair the power supply?
Posted by: Macdrone on 2014-11-14 09:32:34
Depends if you can replace whatever is bad. At this point I found no repair help on mine so I had to do a swap.

If you can see and replace what's bad then maybe you can repair it.
Posted by: ROLLERMANZ on 2014-12-02 01:27:57
hello again guys, its been a while since i opened this forum regarding the Intel Imac powering issue.. i have managed to get hold of this another intel imac which is 17".. i will be collecting this imac sometime later today. this imac has a faulty screen.. the reason I am buying this is so i can exchange the power supllies so that my 20" intel imac can come back to life.. 

do you guys think this method would work even though the one i am getting today is 17" and the one i wana bring back to life is 20" .. see the images of the 17" attached to this post please .. would the 17" have the same kind of power supply and also is it the same model imac as mine? 

2014-12-01 20.00.49.jpg

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Posted by: ROLLERMANZ on 2014-12-02 01:53:11
the guy just sent another image of the imac specifying its specs.. the imac is a 1.83ghz 512mb ram168gb hard drive and its serial starts from w8602.. this does prove its an intel imac right?my 20" imac serial starts as w8603 ...?
Posted by: Macdrone on 2014-12-02 06:45:18
Both the G5 donor power supply and Intel i used had same size screen. I'm not sure but the ALS Mac has a different power supply it's modular and is at the bottom, where as the Intel is on a board up in a corner.
Posted by: ROLLERMANZ on 2014-12-02 11:23:49
So is this good to go
Posted by: Macdrone on 2014-12-02 12:50:53
I'm not sure I had both apart in front of me when I did it.

If he will pull the front off you could know.
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