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macrocosm
Sep 12, 2006, 03:40 AM
I have an iMac G4/800 MHz/256 MB RAM/SuperDrive/60 GB HDD/GeForce2MX, bought in February 2002.

Recently the PSU died and now I have bought an ATX PSU 400W (thats all I could get).

Now I have to modify the ATX PSU to connect it to the main power connector on the Logic Board.

As far as I know, the connector is a 14-pin one and looks like this:
WITH THE CLIP ON TOP

RED, +5v, to HDD | YELLOW, +12v, to HDD | BLUE | YELLOW, +12v | YELLOW, +12v | YELLOW, +12v | YELLOW, +12v

BLACK, COM, to HDD | BLACK, COM, to HDD | WHITE | BLACK, COM | BLACK, COM | BLACK, COM | BLACK, COM

The only thing I can't figure out are the voltages of the BLUE and WHITE wires.

Does any one have a complete pinout for this model ?

I wasn't able to get one even with much googling.

Apple follows different color coding methods for different models of PSUs (I think).

I have connected the YELLOW (+12v) and BLACK (COM) from the ATX PSU to the iMac's main connector.

The iMac seems to show signs of life.

The only ones remaining are the BLUE and WHITE wires.

PLEASE HELP.



macrocosm
Sep 12, 2006, 06:04 AM
I have an iMac G4/800 MHz/256 MB RAM/SuperDrive/60 GB HDD/GeForce2MX, bought in February 2002.

Recently the PSU died and now I have bought an ATX PSU 400W (thats all I could get).

Now I have to modify the ATX PSU to connect it to the main power connector on the Logic Board.

As far as I know, the connector is a 14-pin one and looks like this:
WITH THE CLIP ON TOP

RED, +5v, to HDD | YELLOW, +12v, to HDD | BLUE | YELLOW, +12v | YELLOW, +12v | YELLOW, +12v | YELLOW, +12v

BLACK, COM, to HDD | BLACK, COM, to HDD | WHITE | BLACK, COM | BLACK, COM | BLACK, COM | BLACK, COM

The only thing I can't figure out are the voltages of the BLUE and WHITE wires.

Does any one have a complete pinout for this model ?

I wasn't able to get one even with much googling.

Apple follows different color coding methods for different models of PSUs (I think).

I have connected the YELLOW (+12v) and BLACK (COM) from the ATX PSU to the iMac's main connector.

The iMac seems to show signs of life.

The only ones remaining are the BLUE and WHITE wires.

PLEASE HELP.


no replies yet ?

could someone help please ?

you only need to check the blue and white wires with a multimeter on a similar PSU that is alive.

thanks in advance.

xebra
Sep 12, 2006, 06:15 AM
http://www.xlr8yourmac.com/systems/ATX_G4_AGP_conversion/G4_AGP_to_ATX_case_pg2.htm#next

iMeowbot
Sep 12, 2006, 06:26 AM
I'm not going to be dissecting any lamps soon, but check out this Applefritter thread (http://www.applefritter.com/node/10729) for leads.

macrocosm
Sep 12, 2006, 06:33 AM
I'm not going to be dissecting any lamps soon, but check out this Applefritter thread (http://www.applefritter.com/node/10729) for leads.


thanks friend, but i want to make sure whether the BLUE wire is +3.3v and the WHITE wire +12v.

could you get this confirmed somewhere ?

iMeowbot
Sep 12, 2006, 06:37 AM
I was thinking that maybe you could pop into that forum and ask for details, since there are a few people there who have already gone through the type of conversion you are undertaking.

macrocosm
Sep 12, 2006, 06:38 AM
http://www.xlr8yourmac.com/systems/ATX_G4_AGP_conversion/G4_AGP_to_ATX_case_pg2.htm#next


thanks for taking the trouble xebra,
unfortunately the PSU of the PowerMac is different from the iMac's.

Mine is the lamp shaped iMac, the one that looks like a volleyball at the base and a sunflower on top.

do you know anyone who has disassembled that kind of iMac before ?

baxterbrittle
Sep 12, 2006, 06:51 AM
Okay for a start, why not get an original PSU for an iMac - they are more expensive than an ATX but still not that expensive. Second this is a rumor forum and although there are normally plenty of other discussions going on it is probably not the best place for such a specific query. You should hop on over to www.macmod.com - they are very knowledgable and should be able to help you out.

I'm sure quite a few people on MR have taken apart lamp iMacs but very few will have tested the voltages on particular pins and fewer still will have them memorised.

Sorry to sound blunt that is not my intention - this simply isn't the best place for this kind of thing. Good luck with the Mod.