Jim Phillips <[log in to unmask]> wrote in message news:<[log in to unmask]>...

Hi, Jim
Usually the switching power supply checks the power voltage from
secondary and if power_good signal is missing, It automatically shut
off DC switching circuit within short period time to prevent future
power damage. It sound like Moving one place to the another to make a
power_good signal to Ok? Perhaps, something wrong within the secondary
circuit, like overloading the circuit?

Memory from 21MX switching power supply. ;-)

BTW: Yellow:12V, Red:5V, Black-Return

Peter Chong
Sr. ERP Analyst VB/Oracle

> Well, here is my off-topic post for this week:
>
> In my spare time I am sometimes called upon to troubleshoot PC problems
> (hey, all computers are the same, right?).  Usually the problem can be
> traced to operator error, or bad device drivers, but this one has me
> stumped.  A friend of mine has a PC that will occasionally refuse to power
> on.  I was there when it happened and we disassembled the PC, removed the
> power supply and opened it up.  Checking with a volt-meter showed that there
> was 120 VAC being supplied on the input side and 5 VDC on some of the output
> lines (it's hard to tell which of all those little wires should have power
> and which should not); however, the PC refuses to start up - not even the
> power LED is lit.  We checked the power supply from another PC (already
> removed) and what it does when plugged in is the cooling fan (on the power
> supply) will spin about half a turn and then everything stops.  I've checked
> this at both the surge suppressor and directly from the wall outlet.  The
> wall outlet is on a normally fused line; that is, no GFCI or anything like
> that.  There is another PC located in another area (this is a veterinarian's
> office) that works fine.  However, that's not the odd part....
>
> The remedy for this problem is to take the PC for a walk - literally.  My
> friend disconnects the monitor, keyboard, etc. and takes the system unit
> from outlet to outlet until she finds one that the PC will power up from and
> then the PC is fine...until the next time, which may be several days or
> weeks.
>
> Since this is a vet's office, I am hesitant to suggest sacrificing small,
> furry animals (although she probably knows of some she wouldn't mind getting
> rid of), so any other ideas are welcome.  Thanks.

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