power supply

  • Thread starter Thread starter Lindy
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Lindy

Built my first computer 9 months ago, using an Antec true power 430 watt
power supply, suddenly the fans have quit running, all the voltages to the
board and drives seem to be correct, as there is no problem running the
computer. Any idea why the fans would just quit? and it seems that I read on
this group that there was a way to test power supplies by jumpering across
some pins, anyone know what these are, and will fans run if this is done on
a known good supply? Thanks for any help.
 
Hi. If you are talking about the cpu and system fans(not PSU fans) then you
may have burnt out the mobo fan headers. Have you been running any high
speed fans on the cpu? The fan headers can only take so much current draw
and some high speed fans can over do it. Anyway, just a thought.
..................Chris
 
"Lindy" said:
Built my first computer 9 months ago, using an Antec true power 430 watt
power supply, suddenly the fans have quit running, all the voltages to the
board and drives seem to be correct, as there is no problem running the
computer. Any idea why the fans would just quit? and it seems that I read on
this group that there was a way to test power supplies by jumpering across
some pins, anyone know what these are, and will fans run if this is done on
a known good supply? Thanks for any help.
Click to expand...

To test a power supply, see page 19 of this doc:

http://www.formfactors.org/developer/specs/atx/atx2_1.pdf

This will give you the pinout of the main connector.
To operate the power supply, jumper PS_ON# to COM. PS_ON# is active
low.

Your power supply will have a minimum current spec
on some of the rails. What I did was buy a bunch of 5 watt power
resistors from my local electronics store (not Radio Shack), plus
I got some individual pins that are designed to fit into the
power supply connector. Using combinations of these resistors
(in some cases 4 resistors, to help dissipate the power), I made
some very light dummy loads. The purpose of the dummy loads is
to help the power supply stay in regulation. Without the loads,
sometimes the power supply will give a slightly wrong voltage,
which invalidates the test. For example, if the +12V says 1A
minimum, then 12V/1A = 12 ohms, and I use (4) 3.3ohm resistors
in series. Each resistor dissipates 3.3ohms * 1A = 3.3 Watts
and the resistors are rated for 5W. I use a 12V fan blowing over
the resistors to keep the temperature down. With the loads in
place, you can then measure the voltages with a voltmeter.

To measure the PS at full power is not practical, unless
you happened to inherit some really big power resistors.
Prices at Newark range from $10 to $100 a piece.

Probably easier to RMA it.

Paul
 
Paul said:
To test a power supply, see page 19 of this doc:

http://www.formfactors.org/developer/specs/atx/atx2_1.pdf

This will give you the pinout of the main connector.
To operate the power supply, jumper PS_ON# to COM. PS_ON# is active
low.

Your power supply will have a minimum current spec
on some of the rails. What I did was buy a bunch of 5 watt power
resistors from my local electronics store (not Radio Shack), plus
I got some individual pins that are designed to fit into the
power supply connector. Using combinations of these resistors
(in some cases 4 resistors, to help dissipate the power), I made
some very light dummy loads. The purpose of the dummy loads is
to help the power supply stay in regulation. Without the loads,
sometimes the power supply will give a slightly wrong voltage,
which invalidates the test. For example, if the +12V says 1A
minimum, then 12V/1A = 12 ohms, and I use (4) 3.3ohm resistors
in series. Each resistor dissipates 3.3ohms * 1A = 3.3 Watts
and the resistors are rated for 5W. I use a 12V fan blowing over
the resistors to keep the temperature down. With the loads in
place, you can then measure the voltages with a voltmeter.

To measure the PS at full power is not practical, unless
you happened to inherit some really big power resistors.
Prices at Newark range from $10 to $100 a piece.

Probably easier to RMA it.

Paul<
Click to expand...






Antec sells a power supply tester for $15 USD but I don't know how
comprehensive a test it performs.
 
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