On 27 Mar 2004 at 15:39, Carol wrote:

> I just proved that idea wrong - that the power supply had to be good if the
> fans are working.  My fan within my power supply was running just fine, but
> it was making a lot of noise and I was having all sorts of computer program
> glitches because of the bad power supply -

  A power supply converts the AC from the wall (usually about 120v in North
America) into the 5v and 12v DC needed by the motherboard and internal
peripherals.
  What's not obvious from that is that a maker of power supplies is free to
choose whether the PS fan runs off the AC or the DC side.  If they pick the
AC side -- and many do -- then the behaviour of the PS fan tells absolutely
nothing about the quantity or quality of power on the DC side.

  Motherboard and case fans practically always run off DC, but the power
supply fan is an exceptional case.

David Gillett

                  Visit our website regularly for FAQs,
               articles, how-to's, tech tips and much more
                          http://freepctech.com