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PSU: IIcx & PM7100 Compatibility
Posted by: ArmorAlley on 2017-08-21 10:14:40
Hello everybody,

 It seems that I took the PSU from IIcx in and out too often (I was investigating floppy problems). The machine won't start any more. A member here suggested that I could use a PSU from a PM7100 (of which I happen to have one lying around).

 Both PSUs have the same form-factors, both are made by Astec and the details are as follows:

Thing being measured       IIcx             PM7100

Model Number                  AA15830      AA16870

Made in                            Malaysia      The Philippines

Apple Part No.                  699-0392     614-0009

Output: +5V                     (both) 1mA Continuous

Output: +5V                     12A               15A

Output: -12V                    1.0A              0.6A

Output: +12V                    1.5A             2.5A

Input                                (both) 100-240V; 50-60 Hz; 6A

(AC output) Receptacle     (both) 100-240V; 50-60 Hz; 3A

Is it safe/wise to use the PM7100 PSU in the IIcx?

My gut-feeling says no, but when others have done it without damage to the PSU or motherboard, then I'll give it ago. The IIcx motherboard was re-capped by He-whose-Name-is-not-spoken-of-around-here-no-more some summers ago.

Thanks very much all,

aa

Posted by: Compgeke on 2017-08-21 12:13:36
Yes. IIcx, IIci, IIsi, IIvx, Quadra 700, Quadra 650 and Powermac 7100 all use the same power supply. 

Posted by: Unknown_K on 2017-08-21 13:27:13
I know the Q650 and 7100 are the same.

IIsi is not even the same shape as the others and the ratings are different.

Posted by: 360alaska on 2017-08-21 13:56:14
Higher amp rating means higher capacity, it doesn't mean the IIcx will use more amps. It's like if I took a standard Pc and replaced a 500 watts ATX PS with a 1000watts , it doesn't mean that the computer now uses 1000 watts. Make sense? The main reason the 7100 PS is higher rated is to power the internal CD-ROM. All that matters is that it has the same pinout. I hope that answers your question.

Regards,

Josh

Posted by: ArmorAlley on 2017-08-21 23:07:09
Hi Josh,

 Thanks for the explanation. I tend towards caution in matters electrical. For all I know, the extra ampage may cause the capacitors to blow because they weren't rated for it.

Anyway, I'll try it tonight.

Thanks all,

aa

Posted by: unity on 2017-08-22 00:02:18
^ Does not work that way. This is DC not AC outputs.

Posted by: IlikeTech on 2017-08-22 04:36:43
All that the higher current ratings mean is that the power supply can provide that much power. The computer doesn't have to use it.

Posted by: ArmorAlley on 2017-08-22 11:11:49
Thanks to all who answered and explained. I transplanted the PSU from the PM7100 into the IIcx and it worked. The IIcx came to life again.

Posted by: trag on 2017-08-22 13:34:51
Just replace IIsi with IIvi in Compgeke's list and it's good.   Also, while the IIsi power supply is the wrong shape to be used in the other machines, outside the case, on the bench, one can use a IIsi power supply to boot up the other logic boards and vice versa.   The power connectors are compatible.

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