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agentmommy

macrumors newbie
Original poster
Nov 2, 2009
7
0
Specs:
iMac G5 Intel Core Duo (early 2006).

This has been going on for about 2 months at first only occasionally, now everyday.

The computer won't power up. When it does, sometimes the DVD spins, but the screen stays black and it just hangs there, other times the speakers crackles horribly and it keeps playing the first sound chime over and over. Other times it starts up ok, then suddenly restarts itself.

I've run through all hardware tests it says no trouble is found. I've run through Disk Utility and permissions keep getting rewritten when it restarts, no matter how many times I repair them. I unplug and replug, I've visited all the sites I can for reading up on support, but at this point, I think I might have a power supply issue or logicboard problem... Now it is a crapshoot as to whether it will boot or not, leaning toward not (85% of the time). I have to keep trying to get it going, but then at other times it just dies out and then nada for a while.

Does anyone know how I can diagnose and repair without spending a fortune? Since it's not new the warranty has long expired.

Thanks.
 

MTI

macrumors 65816
Feb 17, 2009
1,108
6
Scottsdale, AZ
First, you're mixing systems . . . there's no G5 Intel Core Duo. ;)

The Early 2006 iMac is an Intel Core Duo.

With regard to the dark screen and the repeating start chime, does the light in the lower right corner of the screen go dim/dark when that happens?

I had a unit do that and it turned out to be a failed memory module. I would suggest removing/swapping one at a time and see if it boots consistently with a single SODIMM module or known good ones.
 

Hellhammer

Moderator emeritus
Dec 10, 2008
22,164
582
Finland
Sounds like logic board, PSU or display issue... Try what MTI recommended, it may help. Here is my guide what to do if your Mac doesn't boot (I have a PDF of it too if you want).

Also, when it works, have you tried sleeping it? Then you would not have to fight with the boot up issue everyday
 

agentmommy

macrumors newbie
Original poster
Nov 2, 2009
7
0
I have not had a chance to try your solutions as now it won't even power on. Hasn't powered on in two days... I've been trying regularly. Not even a smidgeon of a fan whir... nothing. Do I need to open it up? I don't know how to open it... how do I troubleshoot if it doesn't even power on?

If when I run hardware tests and it tells me no trouble was found, what does the hardware test not test that could be wrong? PSU/logicboard/memory modules?

How much to PSU/logicboard cost to replace and how much would I wind up spending on the service alone (I can always take it somewhere like compUSA, I don't need to send it to Apple, they cost a fortune usually). Since I am just south of the Mex border, taking computers across the border is a pain. That's why I was trying to find a solution without having to take it 5 miles north to the US, something DIY that I might be able to just follow instructions and do myself...

IBM has instruction manuals for everything on their machines, how to take them apart, what to work on, etc... I was wondering if there was something comparable for this iMac.
 

agentmommy

macrumors newbie
Original poster
Nov 2, 2009
7
0
First, you're mixing systems . . . there's no G5 Intel Core Duo. ;)

The Early 2006 iMac is an Intel Core Duo.
OH! Good to know! :p
With regard to the dark screen and the repeating start chime, does the light in the lower right corner of the screen go dim/dark when that happens?

It did, but it would also restart itself, like it would just lose power and start up again...
I had a unit do that and it turned out to be a failed memory module. I would suggest removing/swapping one at a time and see if it boots consistently with a single SODIMM module or known good ones.

Now that it's not starting at all, should I even bother with removing memory modules? And is there an instruction guide on how to do that if I should try that?

BTW, I appreciate your replies and trying to help me.
 

agentmommy

macrumors newbie
Original poster
Nov 2, 2009
7
0
Sounds like logic board, PSU or display issue... Try what MTI recommended, it may help. Here is my guide what to do if your Mac doesn't boot (I have a PDF of it too if you want).

Also, when it works, have you tried sleeping it? Then you would not have to fight with the boot up issue everyday

I have tried sleeping it. Problem is sometimes I come back and it lost power, so it's dead again...

I registered with your site, btw. :D
 

MTI

macrumors 65816
Feb 17, 2009
1,108
6
Scottsdale, AZ
The memory modules are accessed via a panel on the bottom edge of the iMac. You have to flip it upside down and undo two phillips screws that hold the center panel. With the cover off, pull up the two plastic arms that are on either side of the opening to loosen the modules that are in the two slots. Small fingers helps.
 

agentmommy

macrumors newbie
Original poster
Nov 2, 2009
7
0
The memory modules are accessed via a panel on the bottom edge of the iMac. You have to flip it upside down and undo two phillips screws that hold the center panel. With the cover off, pull up the two plastic arms that are on either side of the opening to loosen the modules that are in the two slots. Small fingers helps.

Ok, attempted taking out memory modules, one at a time, trying each one, but the power doesn't even come on. Not even initializing the smallest spark of life... So is it possible it's the power supply if it's not even powering on? Or could there be other reasons for lack of power?
 

MTI

macrumors 65816
Feb 17, 2009
1,108
6
Scottsdale, AZ
Yes, if you're not even getting power (front light, sounds of fans, HD spin) then you could very well have a bad power supply. First, the good news. Replacement power supplies for the early Intel iMacs are relatively inexpensive. The not so good news, it's a bit of a chore to get to the PSU, since they put it, as you face the LCD, in the upper right corner of the iMac, so you have to pop the rear case, undo the iSight and mic connectors, undo the foil shield, remove the 4 LCD fasteners and unplug the inverter and data cable to access the PSU.
 

agentmommy

macrumors newbie
Original poster
Nov 2, 2009
7
0
Is there an instructional guide on how to do this with little pictures or detailed step by step instructions on how to perform the change?
 

m0dm0d

macrumors newbie
Nov 8, 2009
1
0
Same thing has just happened to mine (2006 intel imac)... odd to find another user with exactly the same problem :(
 

agentmommy

macrumors newbie
Original poster
Nov 2, 2009
7
0
Same thing has just happened to mine (2006 intel imac)... odd to find another user with exactly the same problem :(

Did you get it fixed already or do you need to? If you still need to take it in somewhere, who are you going to have work on it?
 
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