> Situation is a PC type switching supply that is failing, mulitple units.
> Power source is 120VAC, being supplied via a UPS system.
>
> One theory is that the fact there is a 10-20% total harmonic distortion
> present, that this may be an issue.

        PC power supplies are about the cheapest designed electronic components out
there, so anything is possible. With that said, no, I don't believe THD
would do anything to one. The first "step" in these supplies is almost
always a conversion to DC, the harmonics will either be filtered (there's a
big cap there) or simply be rectified.

        I have a feeling the problem might be overloading. The "ratings" given on
cheap PC power supplies are generally a complete joke. If your system is
going to draw 150W I'd go with nothing less then a 300W supply.

        My recommendation? Buy a quality supply (like an Antec) and get one that is
definitely going to power your load properly. TTYL

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