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widget : widget · Dec 16, 2004, 12:11 PM

So, my beloved iMac G3 is as dead as a doornail. An oft recurring problem of the power switch lighting up, but then cutting out before power reaches the display or HD, has reared its ugly head again.

This has been a real bitch - my computer is integral to my freelance and student work. But I ain't giving up hope yet.

In order to keep a record of attempts to repair it, I guessed it would be cool to put all of this into a thread. I'll keep it updated.

Hopefully if you guys have any ideas, you'll lemme know.

Repair Attempt 1

Replaced P-RAM battery. No effect.

Repair Attempt 2

Purchased power board off eBay for $55 (inc shipping). Awaiting arrival.

Possible Repair Attempt 3

New logic board? Or it just better to invest in a new machine?

macaddict0001 · Dec 16, 2004, 02:28 PM

a used machine with the same specs might be a good idea, then you have redundant hardware to fix any problems.

deboerjo · Dec 17, 2004, 03:03 PM

The new power board is likely to fix it, it also might be the analog board. The logic board is likely fine. Tray-loading iMac or slot-loading? If it's a tray-loader and the logic board is indeed fine, an ATX conversion is a snap.

This is my iMac 333, note the dual hard drives, 52x CD burner and 1600x1200 screen resolution

http://home.comcast.net/~deboerjo/ATXiMac2.jpg

ATX conversions with slot-loaders are significantly harder.

-Jon

macaddict0001 · Dec 17, 2004, 09:45 PM

whoa thats a powerimac.

widget : widget · Dec 18, 2004, 11:00 AM

Originally posted by deboerjo:
The new power board is likely to fix it, it also might be the analog board. Tray-loading iMac or slot-loading?

Slot-loader.

http://home.comcast.net/~deboerjo/ATXiMac2.jpg

Rock on.

deboerjo · Dec 19, 2004, 06:40 PM

Originally posted by widget : widget:
Rock on.

Did that after my analog board died, probably same problem as yours. The analog board dying was the best thing that ever happened to my iMac in retrospect, those things are so much more capable when free of that all-in-one chassis.

widget : widget · Dec 22, 2004, 03:47 PM

Okay... so...

Repair 2

The new power supply arrived. Fitted it without a hitch.

But the S.O.B. still won't power up. However, I did notice that the cable connecting the power supply to the hard drive has a small tear in it. Anyone know where I can get hold of one of these (just in case thats the cause).

Nonetheless, I don't know if I'm prepared to start fiddling with analog boards for a 5 year old machine. The prospect of going near CRTs isn't very appealing.

And I'm contemplating whether I should send it into a dealer/Apple.

As always, your thoughts and suggestions are much appreciated.

widget : widget · Dec 24, 2004, 07:16 PM

Screw all of the above.

Just went down to Regents Street (new Apple Store) and picked myself up an new iMac.

Sweet.

MrForgetable · Dec 25, 2004, 03:42 AM

impulse buys are the best

widget : widget · Dec 26, 2004, 09:28 AM

Originally posted by MrForgetable:
impulse buys are the best

I'll say.

Although now the new machine is up and running, I feel pangs of guilt for the old CRT iMac in the corner. She's all purple and burnt out...

Detrius · Dec 26, 2004, 12:41 PM

Originally posted by widget : widget:
Okay... so...

Repair 2

The new power supply arrived. Fitted it without a hitch.

But the S.O.B. still won't power up. However, I did notice that the cable connecting the power supply to the hard drive has a small tear in it. Anyone know where I can get hold of one of these (just in case thats the cause).

That isn't a power supply. That's the down converter board. Those things virtually never go bad. The actual "Power Supply" on the slot loaders is part of the analog/video board.

widget : widget · Dec 27, 2004, 06:59 PM

Originally posted by Detrius:
That isn't a power supply. That's the down converter board. Those things virtually never go bad. The actual "Power Supply" on the slot loaders is part of the analog/video board.

O great. I should've stopped and asked first.

So essentially, the analog board is what needed to be replaced all along. Bummer. I'll see if I can find an old one on eBay some rainy weekend next year...

Detrius · Dec 29, 2004, 01:28 AM

Originally posted by widget : widget:
O great. I should've stopped and asked first.

So essentially, the analog board is what needed to be replaced all along. Bummer. I'll see if I can find an old one on eBay some rainy weekend next year...

The Down Convert Board can cause the issue you are observing, but it is incredibly rare for those boards to go bad. However, once was enough for me to learn to hang on to a spare so that I can verify the Down Converter/Logic Board pair before moving on to the PAV board.

It is VERY common for the PAV boards to fail. However, if you do the replacement yourself (following all proper CRT discharge procedures), you still won't have the software to properly calibrate the display, as this is only available on Service Source as part of MacTest Pro.

widget : widget · Dec 29, 2004, 07:17 PM

Originally posted by Detrius:
The Down Convert Board can cause the issue you are observing, but it is incredibly rare for those boards to go bad. However, once was enough for me to learn to hang on to a spare so that I can verify the Down Converter/Logic Board pair before moving on to the PAV board.

It is VERY common for the PAV boards to fail. However, if you do the replacement yourself (following all proper CRT discharge procedures), you still won't have the software to properly calibrate the display, as this is only available on Service Source as part of MacTest Pro.

So sending it in for repair looks like will be the only way.

I wasn't too keen on going near the CRT. Is it a pricey proceedure if done by an ACT such as yourself?