Question : Problem: Want to change out a PS50223M Power Supply.  Is it OEM requiring special order or is there a suitable replacement or upgrade?

The PS50223M I believe is dying.  I've never replaced a power supply before and am wondering if I need to buy the exact same one which seems to be difficult to find (based on google searches) or is there a suitable replacement/upgrade?

Any help is appreciated.

Answer : Problem: Want to change out a PS50223M Power Supply.  Is it OEM requiring special order or is there a suitable replacement or upgrade?

Your PSU is IBM PN: 74P4405 and FRU: 74P4300
http://www-307.ibm.com/pc/support/site.wss/document.do?lndocid=MIGR-55502

It is a 230 Watt model manufactured by AcBel.
AcBel PN: API2PC33
AcBel is good design but they have been known to use cheap capacitors now and then. Replacing the caps would probably be all you need to restore the unit.

It is not a standard shape but it looks like a standard ATX bolt pattern and a standard ATX 20-pin pinout.
It is extra short with a 'step' in the chassis shape.
There is a short ATX form factor called PS3 that should fit fine only those don't have the step.

http://cfusion.com/parts/api2pc33/

There is also seems to be a HiPro 230 watt model that is interchangeable.
[Has the step. Used in some other IBM machines.]

Yours has:
+5v - 14 amps
+3.3v - 12 amps
+12v - 11 amps
-12v - 0.2 amps
+5vsb - 2.0 amps [AcBel calls it +5vaux]

You can go to more watts as long as the amps for the voltages shown aren't less than what I wrote.

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