can I USE a 7500 power-supply in my BEIGE G3 DESKTOP
- Thread starter chet david
- Start date
I am now upset. 
To rectify being upset you can go get a nice new reliable ATX power supply and make your computer work properly and safely.The new PSU(go with Seasonic or Corsair) will also have higher efficiency and it's power output will be more stable than anything that ever came in an old Mac.
*edit, actually, SATA cards are not much a load and any normal SATA HDD is likely to either use the same amount or less power than ancient SCSI drives.
*edit, actually, SATA cards are not much a load and any normal SATA HDD is likely to either use the same amount or less power than ancient SCSI drives.
Will it lower my power bill? Would be quieter fan?
The 7500 has a different arrangement of signals in the power connector.
The 7500 uses a different power connector -- actually two power connectors, where the ATX in the Beige uses one.
The power connectors have different numbers of pins.
The Beige G3 runs it's power-hungry circuitry on 3.3V where the 7500 uses 5V for those components. Therefore the 7500 has inadequate 3.3V supply for the Beige G3.
In order to turn the power supply 'On' in the 7500 the logic board ties the "Power On" pin to the 5VSB pin. In order to turn the power 'On' in a Beige, the logic board ties the "Power On" pin to Ground.
You may not find a power supply that is the exact shape, but small powerful ATX supplies abound which can be fit into the Beige G3 case. For example this might be close, although the power available is a little low: http://cgi.ebay.com/Gateway-E4000-Small-Form-Factor-P4-Power-Supply-6500696_W0QQitemZ400085097058QQcategoryZ3670QQcmdZViewItemQQ_trksidZp4340.m263QQ_trkparmsZalgo%3DSIC%26its%3DI%252BC%26itu%3DUCI%252BIA%252BUA%252BFICS%252BUFI%252BDDSIC%26otn%3D20%26pmod%3D400102982379%26ps%3D63%26clkid%3D6127263069489856293
And a little shopping on Newegg or at Frys will turn up all kinds of others.
The 7500 uses a different power connector -- actually two power connectors, where the ATX in the Beige uses one.
The power connectors have different numbers of pins.
The Beige G3 runs it's power-hungry circuitry on 3.3V where the 7500 uses 5V for those components. Therefore the 7500 has inadequate 3.3V supply for the Beige G3.
In order to turn the power supply 'On' in the 7500 the logic board ties the "Power On" pin to the 5VSB pin. In order to turn the power 'On' in a Beige, the logic board ties the "Power On" pin to Ground.
You may not find a power supply that is the exact shape, but small powerful ATX supplies abound which can be fit into the Beige G3 case. For example this might be close, although the power available is a little low: http://cgi.ebay.com/Gateway-E4000-Small-Form-Factor-P4-Power-Supply-6500696_W0QQitemZ400085097058QQcategoryZ3670QQcmdZViewItemQQ_trksidZp4340.m263QQ_trkparmsZalgo%3DSIC%26its%3DI%252BC%26itu%3DUCI%252BIA%252BUA%252BFICS%252BUFI%252BDDSIC%26otn%3D20%26pmod%3D400102982379%26ps%3D63%26clkid%3D6127263069489856293
And a little shopping on Newegg or at Frys will turn up all kinds of others.
Very thank you!!
Just realized that the "In order to turn the power supply 'On' the logic board ties the 'Power ON' pin to..." bullet in my previous post may be incomplete.
I wrote that the Beige ties the 'Power On' pin to Ground, but it is possible that in the Beige G3 that depends on the setting of that jumper on the logic board. That may be exactly what that jumper controls -- whether 5VSB or GND is used to trigger 'Power On'.
It is true that a 7500 PS expects 5VSB on 'Power On' as an 'ON' signal and an ATX PS expects GND as an 'ON' signal, but it may be that the Beige G3 logic board can supply either 'ON' signal depending on how the jumper is set.
I'm not sure, but I think that is the case.
I wrote that the Beige ties the 'Power On' pin to Ground, but it is possible that in the Beige G3 that depends on the setting of that jumper on the logic board. That may be exactly what that jumper controls -- whether 5VSB or GND is used to trigger 'Power On'.
It is true that a 7500 PS expects 5VSB on 'Power On' as an 'ON' signal and an ATX PS expects GND as an 'ON' signal, but it may be that the Beige G3 logic board can supply either 'ON' signal depending on how the jumper is set.
I'm not sure, but I think that is the case.
That might be an interesting thing to explore with a meter on a bench just for the sake of finding out.
Does anyone have a handy AIO Beige G3 PSUs to check this? It was the AIOs that used that setting wasn't it? I seem to recall people writing that they just plugged in their ATX PSUs when they were working with the non-AIO ones.
*Edit
Mac Gurus says "Desktop chassis" so I guess that covers the AIO and desktop model while excluding the minitower based one+it's "server" version.
Does anyone have a handy AIO Beige G3 PSUs to check this? It was the AIOs that used that setting wasn't it? I seem to recall people writing that they just plugged in their ATX PSUs when they were working with the non-AIO ones.
*Edit
Mac Gurus says "Desktop chassis" so I guess that covers the AIO and desktop model while excluding the minitower based one+it's "server" version.
I have a working beige g3 power supply i pulled years ago. its floating around here somewhere, i could test the theory with that?
i stripped a G3 desktop years ago. and kept its power supply. the logic board died, which is why i stripped it.
Epic thread is epic.
I really wish I had more to add, but I don't. I just read the whole thread and kinda sat in my chair, stunned.
Will the circle plug into to the square?
No?
Why?
It's a circle, not a square.
But I have a lot of circles, are you sure it won't fit?
Try it.
Bricks.
Um, yeah.
I really wish I had more to add, but I don't. I just read the whole thread and kinda sat in my chair, stunned.
Will the circle plug into to the square?
No?
Why?
It's a circle, not a square.
But I have a lot of circles, are you sure it won't fit?
Try it.
Bricks.
Um, yeah.
Some times, when folks are dealing with stuff new to them, they really need a little extra hand holding. This is especially understandable given the ready availability of wrong information and folks (usually not here) who will answer questions glibly and wrongly.
You can hardly blame a fellow for wanting a little extra exposition and reassurance.
A little patience goes a long ways.
You can hardly blame a fellow for wanting a little extra exposition and reassurance.
A little patience goes a long ways.
