Re: PC doesn't start

On Feb 9, 4:10 am, "Andrea"
<andrea.delzoppo(removethis)@fastwebnet.it> wrote:
Thanks Jim for the advices. I changed the MOBO Battery with no result.
Today, as I did already a few days ago and worked but didn't yesterday, I
disconnected the signal cable of the monitor; the PC started. Cannot say
it's a monitor fault. Any further sugestions?

Stop trying to fix things without first knowing what is wrong. Get a
3.5 digit multimeter (so ubiquitous as to be sold even in K-mart) and
measure some DC voltages from power supply. First is the purple wire
that must measure 4.87 volts DC when computer is not powered on. Then
measure green wire voltage that must be well above 2 volts before
power switch is pressed AND drop to well below 0.8 volts when power
switch is pressed.

Next look at one of each orange, red, and yellow wires when power
switch is pressed. What does each do? Each must exceed 3.23, 4.87,
and 11.7.

Now in less than two minutes, you have numbers that provide a useful
reply; will point to a suspect.

Currently you are shotgunning. Just like firing a gun blindly in
all directions until something changes. What have you learned?
Nothing. You even replaced the battery. Was that defective? We don't
know. But with a meter and less than 30 seconds, you would have know
- and not disconnected or replaced anything. Just another example of
knowing what is bad before replacing anything.

Numbers from those measurements (in less than 2 minutes) should
point to a suspect. And posting those numbers will even provide far
more useful information. Your replies will only be as good as the
information provided. That means numbers from meter measurements.

.

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