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| Click here to select a new forum. | | Power Mac G4 "Quicksilver" 733 | Posted by: Quadraman on 2008-07-06 08:38:56
Are the G4's with ADC supplies built like crap or something? Just seems like they do not last very long, many units just get parted out since nobody wants to pay for a replacement.
I have a feeling that they will be worth a few dollars someday just because of rarity in working condition. No, it's just the proprietary PSU's are so expensive it's usually cheaper just to salvage whatever parts you can and buy another one.
| Posted by: Quadraman on 2008-07-06 08:41:36
You need a Quicksilver power supply. A generic ATX won't work nor will the power supply from any other G4. Expect to pay about $70-$100 on ebay. Yes you can
http://www.outofspec.com/frankenmac/wire.shtml
And from where exactly are you drawing the TWO +28v lines from in a standard ATX PSU? The single +28v line on the Gig Ethernet/ Digital Audio is hard enough, but you definitely aren't getting two of them from a standard ATX no how. Using wallwarts to supply +28v is messy at best. Are you supposed to use two of them with a Quicksilver motherboard? How convenient is that, having a computer with three power cables instead of one? How easy is it to plug two wallwarts into an a two outlet wall plate or power strip/block at the same time? Rewiring an ATX is probably not something most people would be comfortable with, either.
| Posted by: iMac600 on 2008-07-07 03:56:51
And from where exactly are you drawing the TWO +28v lines from in a standard ATX PSU? The single +28v line on the Gig Ethernet/ Digital Audio is hard enough, but you definitely aren't getting two of them from a standard ATX no how. Using wallwarts to supply +28v is messy at best. Are you supposed to use two of them with a Quicksilver motherboard? How convenient is that, having a computer with three power cables instead of one? How easy is it to plug two wallwarts into an a two outlet wall plate or power strip/block at the same time? Rewiring an ATX is probably not something most people would be comfortable with, either. The machine doesn't need the full 28v to start according to the modification guide, on most systems with modified PSU's, 16-17v has been found sufficient.
The simple solution is to connect the 12v+ line from the PSU's molex connector to the 5v+ trickle line to generate a total of 17v. Diodes are of course required.
The conversion guide can be found here, along with conversion guides for all sorts of other G4's.
http://atxg4.com/quicksilver.html
The simple diagram for connecting 12v to the 5v trickle line can be found here.
http://atxg4.com/images/Wiring-DiagramQS.jpg
EDIT: Oh damn, I just realised why it may not be working. The diodes I soldered in are around the wrong way... durr! *hits self* I'll rectify the problem and give it another test.
DOUBLE EDIT: It didn't work even with the diodes in the correct order. I think the tower's dead as a doorstop, so project Silvertooth will go ahead provided I can find a Sawtooth logic board.
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