System powers down at beginning of POST

[Dave]

I had a system given to me today, an ECS L4S5MG3/GX+(5.0) mobo w/2.66
processor, 512mb DDR333 RAM. Unfortunately, it powers down at the beginning
of the POST. I've removed all the cards, unplugged all the drives power,
reseated the DDR ram in the other slot, and reseated the CPU. The only
other response I've been able to get is one long beep if I leave the RAM
out. I cleared the CMOS by jumper and removing the battery and now get the
single beep and the monitor flashes data for just an instant before
everything shuts down, but it's too brief to read. Don't currently have a
power supply to swap. Anyone want to suggest some ideas?

Thanks,
Dave

 

[Richard Urban]

Defective power supply or a short circuit cutting off the power supply.

--


Regards,

Richard Urban
Microsoft MVP Windows Shell/User

Quote from George Ankner:
If you knew as much as you think you know,
You would realize that you don't know what you thought you knew!

 

[Dave]

Defective power supply or a short circuit cutting off the power supply.

Found a compatible power supply out of a Gateway. Same symptoms. But, this
PS has a "test" button. By holding in this button, I was able to access the
CMOS (had a checksum error) and load the safe defaults. Still has the same
symptom, though. This PS would shut down whenever I released the test
button. Tried to load XP in safe mode, but it never went GUI.I did boot a
Partition Manager clone CD and it worked in GUI. Sounds like mobo, doesn't
it? Since video is onboard, this only leaves the CPU.

Dave

 

[nehmo54]

Can you at least check the voltage at the pins? Ground pin 14
http://www.pavouk.comp.cz/hw/en_atxps.html (scroll down), then see what
the leads are putting out.

 

[Dave]

(e-mail address removed) wrote in @o13g2000cwo.googlegroups.com:

Can you at least check the voltage at the pins? Ground pin 14
http://www.pavouk.comp.cz/hw/en_atxps.html (scroll down), then see what
the leads are putting out.

Can you see the egg on my face from there?? Turns out the power switch was
stuck. I thought I had disconnected it, but I has misread the pin numbers.
The hardware's running great and I'm reloading XP as I'm typing now. Thanks
for everyone's suggestions.

Dave