[olug] Hardware problems on an HP desktop

[Bill Brush]

This is just kind of an expansion on why I think it's the power supply.

Although most people aren't aware of it, power supplies are fairly
sophisticated.  There is a circuit in them (called the power good circuit)
which monitors the 5V output.  As long as the output is within tolerance
(which is fairly tight) everything is fine.  If the output falls out of
tolerance the power good circuit shuts off all output.  This prevents the
PS from ruining equipment by supplying too much or too little voltage.

In your case it's entirely possible that the PS is borderline and on some
boots it gets the output within tolerance and some it doesn't.  The
capacitors and inductors in the PS do degrade over time, and in commercial
supplies they aren't the highest quality components to start with since
they have an expected service life of 2 to 3 years.

Bill

olug-bounces at olug.org wrote on 02/23/2004 11:11:59 PM:

> Well, swapping out the memory didn't help.
>
> I've considered the power supply, but I (irrationally?) deduced thatif
there's
> any kind of power to the system, then the power supply must be alright.
> Obviously, Bill, you think otherwise.  I have a spare power supply
> so I'll give
> that a go.
>