Re: Does a ][ power supply ever take out its mobo?

["Michael J. Mahon" <mjmahon@aol.com>]

jsnospam@cimmeri.com wrote:
> Hi Tristan,
>
>    I'm not sure that what happened with your clone II+ would be a
> valid indication of the threat potential from an Apple power supply --
> as the designs might be different.  Would you agree?   Yet, good to
> keep in mind regardless.
>
>    I took your advice and opened the PS to check out the caps.
> Remarkably, they were all fine except ONE.. which was out of ESR spec
> so I replaced it and others of its size (it was one of those small
> axial electrolytics.)
>
>    I then opened up two other II+/IIe power supplies.. and found that
> everyone one had slightly different designs and layouts.  They all
> varied in number of electrolytics.
>
>    What bothers me most about these II power supplies is the lack of
> ventilation and how hot they run... and the presence of some 85c
> electro's in them... AND how the PCB is mounted at the top of the case
> -- where all the heat rises.   Yet despite all these shortcomings, the
> damn things have lasted close to 30 years.

Note that 85C is 185F, and I've never found a power supply case
too hot to hold my hand on (which would be about 140F)...

We always like to have things run cool, but they are well within
their design specs.

-michael

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