Problems with dual Athlons (power; popping breakers)

Michael Stein mas at
Thu Aug 1 07:50:52 PDT 2002

> > One possiblity I've thought of but haven't tried would be to switch the
> > PC power supplies to the 240 setting and run them off of 208 (between
> > two phases of the three phases).
> Be aware the 240V setting is usually rated at 240V +- 5%, or 
> maybe 10%. That is: it will work at old French 230V level. It will
> also work at British 250V. But it may not work well at 208V.
> At the very least keep the wires large bore and short.

A quick search for some (cheap) PC power supply specs shows:

  250 ATX
  Operating range: 95-132 VAC 180-264 VAC (switch)
  47-63 Hz.

So 208 VAC shouldn't be a problem (haven't tried it).
> Your major problem will be frequency. 240V is delivered at 50 Hz - 
> not 60Hz.

  In the US it's all 60 Hz.  Homes are typically 120/240 single phase,
  while business/industrial is 120(wye)/208(delta) three phase.

  Typical switching power supplies don't care, 50 or 60 Hz is

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