in message
VanguardLH,
The power supply is an ATX. Thanks for asking, let me know if there
is an
easy way to see if this power supply has gone bad.
Disconnect the ATX power supply from everything except: power cord to
wall outlet and to 1 hard drive (to provide an internal load).
Obviously you need power to test. The load may be needed by some
power supplies which do not power up if they see no load on their
power taps.
Remove the 20-pin header from the power supply to the motherboard (for
an ATX power supply, 24-pin if an ATX-12 style). Short the PS-ON line
to a ground line. The power supply never completely turns off (unless
you yank the power cord). A 5-volt standby line remains up to power
the logic on the motherboard for powering up the power supply. When
you press the Power switch, that switch is not connected to the power
supply. Instead that switch goes to the motherboard where logic will
drop the PS-ON line to ground to tell the power supply to come up
fully. So basically you are replacing that motherboard logic by
shorting PS-ON to ground at the 20-pin connector. PS-ON is the green
wire (pin 14 for the 20-pin connector). The grounds are the black
wires.
When the power cord is connected to the power supply, there is a load
(by the hard drive), if needed, and with PS-ON shorted to ground, you
should see the power supply come on. That is, you will see its fan
start spinning and the hard drive will spin up. If that works, all
you've proven is that the power supply will come on if told to power
up by PS-ON going low. You still need to measure the voltages at each
of the power taps using a voltmeter or multimeter (and this must be
measured under load so you hook it all back up and then check
voltages).
If PS-ON going low made the power supply come on, reconnect the power
supply but under a minimal load. The power supply should only be
connected to: motherboard and 1 hard drive. CD/DVD drives, floppy
drives, and other components shouldn't be powered. Remove all cards
from the slots except the video card. Remove all but 1 stick of
memory. Check if the host powers up. If it does, check voltages on
the power taps that are used. Then power down, connect the next piece
of hardware, and check if you can power up again. Perhaps you have a
part that is drawing too much power (i.e., it has a short) or you
simply have way too many parts that are consuming more power than the
power supply can supply.
Figure on not getting more than two-thirds of the rated wattage from a
cheap power supply. Rather than doing all the above, and if you don't
feel capable, it might be easier and faster to just get another power
supply but expect to pay for a decent one that actually supplies the
wattage that it is rated for.
Also, you ask: ""Also, how is this a Windows XP question?"" Well,
yes there
are other groups such as hardware. The problem is that very few
people post
on these boards and sometimes it takes awhile to get your questions
answered.
So, I am posting the problem here for a quick response. Hope this is
not a
problem for you.
Doesn't matter if a group is busier than the appropriate one(s).
Would you post in a gardening group if it were busy? Off-topic posts
are spam.
I have crossposted my reply (and set FollowUp-To) to the
microsoft.public.windowsxp.hardware group so go there to continue the
discussion (after testing the power supply).
