Wierd power supply problem

[Philip]

I have a computer with an Antec power supply and a Gigabyte GA-&VTXH
AMD motherboard. When I press the on button the fans power comes on
for a second and then dies. If I press the button again I get no
response. If I unplug the power supply and wait until the LED on the
mother board goes out and then try turning it on it again, it turns on
and dies. Now the fun part. If I disconnect the switch and short the
pins where the switch is plug in for a few seconds, the machine boots
and runs normally. If I hook a meter to the switch it show open. When
I press the button, it shows close until I release the button. So the
switch appears to be good. Is it safe to assume that the power supply
os flacky and needs replacement?

[Pen]

No. Since the machine runs normally with the jumper
the likely culprit is the motherboard. The mobo has
active circuitry between the switch and the power supply
which holds the "on line" low.

"Philip" <phughes200@hotmail.com> wrote in message
news:ba78a0bd.0311121042.572b7828@posting.google.com... I have a computer with an Antec power supply and a Gigabyte GA-&VTXH AMD motherboard. When I press the on button the fans power comes on for a second and then dies. If I press the button again I get no response. If I unplug the power supply and wait until the LED on the mother board goes out and then try turning it on it again, it turns
on and dies. Now the fun part. If I disconnect the switch and short the pins where the switch is plug in for a few seconds, the machine
boots and runs normally. If I hook a meter to the switch it show open.
When I press the button, it shows close until I release the button. So
the switch appears to be good. Is it safe to assume that the power
supply os flacky and needs replacement?

[Michael Hawes]

>>No. Since the machine runs normally with the jumperthe likely culprit is the motherboard. The mobo hasactive circuitry between the switch and the power supplywhich holds the "on line" low.

"Philip" <phughes200@hotmail.com> wrote in message
news:ba78a0bd.0311121042.572b7828@posting.google.com... I have a computer with an Antec power supply and a Gigabyte GA-&VTXH AMD motherboard. When I press the on button the fans power comes on for a second and then dies. If I press the button again I get no response. If I unplug the power supply and wait until the LED on the mother board goes out and then try turning it on it again, it turns
on and dies. Now the fun part. If I disconnect the switch and short the pins where the switch is plug in for a few seconds, the machine
boots and runs normally. If I hook a meter to the switch it show open.
When I press the button, it shows close until I release the button. So
the switch appears to be good. Is it safe to assume that the power
supply os flacky and needs replacement?

It's cheaper to try a new switch first. :-)

Mike.





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[Charles Howse]

Previously Philip <phughes200@hotmail.com> wrote: I have a computer with an Antec power supply and a Gigabyte GA-&VTXH AMD motherboard. When I press the on button the fans power comes on for a second and then dies. If I press the button again I get no response. If I unplug the power supply and wait until the LED on the mother board goes out and then try turning it on it again, it turns on and dies. Now the fun part. If I disconnect the switch and short the pins where the switch is plug in for a few seconds, the machine boots and runs normally. If I hook a meter to the switch it show open. When I press the button, it shows close until I release the button. So the switch appears to be good. Is it safe to assume that the power supply os flacky and needs replacement?

Sounds like a switch that closes badly and sends several pulses to
the mainboard. A simple meter would not show that.

Replace the switch.

Arno
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[Philip]

I tried replacing the switch. That didn't fix it. I ended up replacing
the power supply. With a new power supply and the orginal switch,
everything works. I am suprised that the Antec power supply lasted
only two years. The new has a three year warranty.

phughes200@hotmail.com (Philip) wrote in message news:<ba78a0bd.0311121042.572b7828@posting.google.com>... I have a computer with an Antec power supply and a Gigabyte GA-&VTXH AMD motherboard. When I press the on button the fans power comes on for a second and then dies. If I press the button again I get no response. If I unplug the power supply and wait until the LED on the mother board goes out and then try turning it on it again, it turns on and dies. Now the fun part. If I disconnect the switch and short the pins where the switch is plug in for a few seconds, the machine boots and runs normally. If I hook a meter to the switch it show open. When I press the button, it shows close until I release the button. So the switch appears to be good. Is it safe to assume that the power supply os flacky and needs replacement?