How to diagnose a dead PS?

In article ,
says...
I have what I think is a dead power supply. There are no lights or any sign
of activity anymore. Normally there is a ASUS P5E MB LED on even when the
PS if off. No response to the power button at all. Completely inert. No
fans, no lights, no nothing.

To make sure it's the PS, is there a voltage on one of the PS connectors
that is ALWAYS present that I can check for to see if the PS is producing
anything at all? I recently upgaded to all new parts so both the PS and MB
are relatively new.

Thanks.
Bruce.

I usually start with the sniff test. If they smell like magic smoke
I toss them. After that I swap another power supply in it's place.
If it works I toss the bad one. If it doesn't, look elsewhere for
your problem.

Bill

"Bill" wrote in message
news:MPG.22f01613a1ec75749898db@localhost...
I usually start with the sniff test. If they smell like magic smoke
I toss them. After that I swap another power supply in it's place.
If it works I toss the bad one. If it doesn't, look elsewhere for
your problem.

Good suggestion! I tried that but it my PS I can't detect any odor at all.
I hope that isn't a bad sign for my diagnosis. I'll find out tomorrow.

Bruce.

"mr deo" wrote in message
m...
Been a long time since I used american sockets, all of the plugs you find
in
europe are fused, I seem to recall that nearly all nema plugs had no
fuse..

I sure wish PCs came with fuses. That might have saved me a lot of grief.
I still have a supply of 3AG type fuses in the basement but I can't even
remember the last time I needed one.

Checking for the +5v as mentioned earlier is real important, as "typically
speaking" most of the internal controls are ran from that +5v..

I measured from the GND pins to several other pins, including the +5, and +5
Standby and nothing.

I would (for kicks) just use the same power plug on your monitor and make
sure that all is well there.. for such a new supply it's not worth opening
it as you should be able to get a warranty replacement.

Yes, as tempting as is is, I'm not going to open it. Newegg will replace it
for a year so that's what I'm going to do.

Thanks.

Bruce.

On Jul 22, 8:37 pm, "Bruce." wrote:
Good suggestion! I tried that but it my PS I can't detect any odor at all.
I hope that isn't a bad sign for my diagnosis. I'll find out tomorrow.

All those tests including smell, paper clip, or the motherboard LED
reports almost nothing. LED says AC power cord is connected. Nothing
more. +5VSB can be completely defective and still that light will
glow.

Nothing identifies something faster than the 3.5 digit multimeter.
In less than a minute, the suspect could have been identified without
shotgunning. Shotgunning: buying a power supply only on
speculation. Did you know about other components of the power supply
'system' - other parts that could have failed?

In your case, meter measures voltage on purple, green, and gray wire
both before and when power button is pressed. What those numbers
report means either you know exactly what is defective OR what to look
at next. Also useful are DC voltage on any one of orange, red, and
yellow wires as power button is pressed.

Normal is for a new power supply to boot a system and still be
defective. Just another reason to have that meter. Once the system
boots, access every peripheral simultaneously - multitask. Then
measure voltages on any one of purple, orange, red, and yellow wires.
Numbers must exceed 3.23, 4.87, and 11.7. If less, a defective power
supply is booting the computer. Meter is also how to identify and
eliminate failures long before the warranty expires. Meter reports
everything that the LED, paper clip, or smell might report - and more
- and faster.

"Bruce." wrote in message
...
I have what I think is a dead power supply.

Thanks to everyone for your comments and troubleshooting tips. Everything
confirmed my fears that I had a bad supply.

The good news is I had a replacement overnighted from Newegg and it's in and
working. I'm unhappy that the Corsair failed after just 7 weeks but I'm
running again now.

Bruce.

Just FYI. While working on this I discovered something weird. The ASUS
P5E comes with a sound card that plugs to a slot. The sound card has a
fancy logo on top that is back illuminated by a blue LED. What's weird is
the designers desided to run that LED off the +5 Standby voltage rather than
the main +5. As a result the card is lit up even when the computer is off.

I guess they wanted all those owners to see their card through their
transparent side windows even when powered down. I guess the draw of an LED
is small so why not.

Anyway, now that the new PS is in, the motherboard LED and soundcard LED are
nicely lit up again.

Bruce.

On Tue, 22 Jul 2008 17:25:47 -0400, "RobV"
wrote:

No sign of any activity at all, ao I've ordered a PSU replacement for
it. This Corsair 620 PSU was only about 7 weeks old.

Thanks.

Yeah, it's the PSU then. No decent power supply should fail that soon.
I've used Antec PSUs for years and the oldest one, about 6 years old, is
still working fine. I'm not advocating Antec PSUs, just commenting that
a good PSU should last for years. Good luck and you're welcome.

In general Corsair have very very good PSU-s, and will be a brand I
normaly recommend. I personally have systems with Corsair VX450,
VX550, HX520 and HX750. I belive for most models, Corsair have used
Seasonic as the designer/manufacturer.

Antec normaly gives a good combination of quality, noise level and
price.




--
Clas Mehus
- "Den som har flest prylar när han dör vinner..."

On Tue, 22 Jul 2008 17:07:48 -0500, "Bruce."
wrote:


But in this case I don't know if it was a line surge or a PS that went bad,
or maybe both. Since it's only 7 weeks old, I suspect it was a defective
PS.

I guess it will we a warrenty-deal. My recommendation will be to stay
away from opening the PSU and "do stuff" unless you really know what
you are doing.... :-\




--
Clas Mehus
- "Den som har flest prylar när han dör vinner..."

"Clas Mehus" wrote in message
...
I guess it will we a warrenty-deal. My recommendation will be to stay
away from opening the PSU and "do stuff" unless you really know what
you are doing.... :-\

I agree. While I do know my way around electronic circuitry, there's
usually no point in opening a PC power supply that's gone bad unless you're
prepared to replace the fried components.

A while back I had a lightening strike that fried a PS. I opened it hoping
I might find a blown internal fuse. As I opened it, part of an exploded
power transistor fell out. I immediately ordered a replacement supply. :-)

This one was still under the Newegg replacement warrantee so that was
another excellent reason not to open it.

My replacement supply arrived and it resolved the problem.

Thanks.

Bruce.