As you could undoubtedly surmise for yourself, a different PSU case implies nothing about the contents. The IIsi is certainly of its breed, and derived from the IIci, but does it have an auto-restart switch? Absence of that could make a difference. Not even a site such as this has much info. about PSU design. Showbaffum wrote that he didn't know of any schematics, but you may be able to do better than that if you can catch tomlee59's eye.

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