PC Smoke

[OG]

Quad Core Desktop Windows 7 PC been running for several days.
Today plug and unplugged USB drives to make a copy to USB Drive.

Started the copy and the screen went blank and the room filled with
smoke. Smelled like burning resistor (I think). I have smelled that
smell before.

Turned off the PC power.
Turned on the fans to get the smoke out.
Smoke detectors did not alert.

What are typical failures to look for?

Please give suggestions.
First I need to figure out how to get the cover off.

--- news://freenews.netfront.net/ - complaints: news@netfront.net ---

 

[philo]

On 05/03/2016 12:49 PM, OG wrote:

Quad Core Desktop Windows 7 PC been running for several days.
Today plug and unplugged USB drives to make a copy to USB Drive.

Started the copy and the screen went blank and the room filled with
smoke. Smelled like burning resistor (I think). I have smelled that
smell before.

Turned off the PC power.
Turned on the fans to get the smoke out.
Smoke detectors did not alert.

What are typical failures to look for?

Please give suggestions.
First I need to figure out how to get the cover off.
X

When you open the case it will probably be obvious.

If you do not see any burned, it's probably the power supply.

 

[John Robertson]

On 05/03/2016 10:49 AM, OG wrote:

Quad Core Desktop Windows 7 PC been running for several days.
Today plug and unplugged USB drives to make a copy to USB Drive.

Started the copy and the screen went blank and the room filled with
smoke. Smelled like burning resistor (I think). I have smelled that
smell before.

Turned off the PC power.
Turned on the fans to get the smoke out.
Smoke detectors did not alert.

What are typical failures to look for?

Please give suggestions.
First I need to figure out how to get the cover off.

--- news://freenews.netfront.net/ - complaints: news@netfront.net ---

Your eyes and nose are going to be your biggest help after you get the
box open. Of course the machine is UNPLUGGED when you are taking it apart.

I would talk to your local dealer...can be a bad power supply (most
common failure).

John :-#)#

--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9
(604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."

 

[OG]

There a sound level detectors for locating sound.
There are infrared detectors for location heat.
There are volt meters for detecting voltages.
There are scopes for detecting waveforms.

Are there smell detectors for locating burned components?

 

[philo]

On 05/03/2016 01:43 PM, OG wrote:

There a sound level detectors for locating sound.
There are infrared detectors for location heat.
There are volt meters for detecting voltages.
There are scopes for detecting waveforms.

Are there smell detectors for locating burned components?

Yes. Your eyes

 

[Mike Easter]

philo wrote:

OG wrote:
Quad Core Desktop Windows 7 PC been running for several days.

Does that several days mean that it is 'brand new' - those several days
are the entire time you've had it?

Today plug and unplugged USB drives to make a copy to USB Drive.

Started the copy and the screen went blank and the room filled with
smoke.

Whoa! That must've been some pretty hot stuff you were copying

>> What are typical failures to look for?

Philo's PS sounds like a candidate.

Please give suggestions.
First I need to figure out how to get the cover off.

If it is an OEM, naming the brand/modelno would be helpful to guide the
case business.

When you open the case it will probably be obvious.

If you do not see any burned, it's probably the power supply.

Yeah.

--
Mike Easter

 

[MJC]

In article <ngarhd$141a$1@gioia.aioe.org>, AIEO@AIOESPAM.COM says...

There a sound level detectors for locating sound.
There are infrared detectors for location heat.
There are volt meters for detecting voltages.
There are scopes for detecting waveforms.

Are there smell detectors for locating burned components?

Not sure whether you'd want a dog or a canary!

Mike.

 

[FromTheRafters]

OG formulated the question :

Quad Core Desktop Windows 7 PC been running for several days.
Today plug and unplugged USB drives to make a copy to USB Drive.

Started the copy and the screen went blank and the room filled with smoke.
Smelled like burning resistor (I think). I have smelled that smell before.

Turned off the PC power.
Turned on the fans to get the smoke out.
Smoke detectors did not alert.

What are typical failures to look for?

Please give suggestions.
First I need to figure out how to get the cover off.

--- news://freenews.netfront.net/ - complaints: news@netfront.net ---

Burned run on the PCB?

 

[FromTheRafters]

After serious thinking philo wrote :

On 05/03/2016 01:43 PM, OG wrote:
There a sound level detectors for locating sound.
There are infrared detectors for location heat.
There are volt meters for detecting voltages.
There are scopes for detecting waveforms.

Are there smell detectors for locating burned components?





Yes. Your eyes

Exactly, look for smoke residue. This may be problematic if 'smoke
filled the room' was not hyperbole.

 

[Mayayana]

| Started the copy and the screen went blank and the room filled with
| smoke. Smelled like burning resistor (I think). I have smelled that
| smell before.
|
The only time I've ever seen that happen was with
some kind of short that caused smoke and then soon
after a resistor exploded. It overloaded all components,
killing the RAM, hard disk, modem, CPU. Do not try
to turn it on again. If there's anything left usable it
should be removed and oput into a new box if possible.
You could try just replacing the power supply, but I
wouldn't do that with a valuable hard disk in place.

 

[Paul]

OG wrote:

Quad Core Desktop Windows 7 PC been running for several days.
Today plug and unplugged USB drives to make a copy to USB Drive.

Started the copy and the screen went blank and the room filled with
smoke. Smelled like burning resistor (I think). I have smelled that
smell before.

Turned off the PC power.
Turned on the fans to get the smoke out.
Smoke detectors did not alert.

What are typical failures to look for?

Please give suggestions.
First I need to figure out how to get the cover off.

Power supply.

*******

There is one chipset with a problem, then your source
would be motherboard. The Intel ICH5/ICH5R could suffer
latchup in the USB I/O area. Causing a short across the
rails powering th USB pads. In an unlucky case, the bond
wires on the pad with the latchup, remain intact, and
a burned spot appears on the lid of the Southbridge.
Since the Southbridge in that case, has no heatsink,
it's easy to spot when someone tells you where to look.

(What a damaged ICH5/ICH5R looks like...)
http://i.onfinite.com/TFG42bkgd.jpg

But that hasn't happened since ICH5 era - no PCH seems
to have suffered a similar fate. So Intel quietly figured
it out. Back when those were happening, there might
have been around 30 USENET posts from victims... I still
own an ICH5, which remains intact. And I treat it
like royalty

*******

If you were to take it to Geek Squad, they might well
immediately pull the ATX supply, and connect up a
spare supply. This is fine, if the spare is a decent
name brand supply with full protections (so it can
survive whatever the motherboard throws at it). But
there might be a flaw which can damage a spare
supply (like some rail to rail short maybe).

A question arises occasionally "should I try to use
the defective computer again and again to collect
more (smoky) symptoms?" . No, don't do that. One
poster tried that while debugging his system,
and the old flaky supply blew in spectacular fashion,
damaging the motherboard. Meaning the repair went from
from costing $50, to costing $200.

You can at least start with the "nose" test, and
track down where the smoke came from. And PSU
is likely to be the source.

Visual inspection only occasionally digs up a root
cause for you. But visual inspection is cheap. And
visual inspection is safe, *as long as you stay
away from high voltage stuff*. The inside of the
ATX supply, below the lid with the four screws,
has a couple caps that are (potentially) dangerous.
They hold enough energy, you *do not* use the screwdriver
discharge method on them - it would deafen you if
you tried that. Just stay away from them.

There is a reference schematic for a simple ATX power
supply design here. R2 and R3 make C5 and C6 "safe". But
if R2 or R3 fail open circuit, then the natural draining
process provided by R2 and R3, might not actually be
protecting you from high voltage. It is C5 and C6 terminals
on the PCB, you do not want to touch... Only use
a proper resistive shorting technique to make them
safe (i.e. connect your own R2 and R3). It's better
just to "look but don't touch" while looking inside
an ATX supply... And don't forget to unplug the computer!!!

http://www.pavouk.org/hw/en_atxps.html

When you visually inspect the inside of an ATX
supply, this is what you'd be looking for.
I had an Antec, with low service hours, that
looked exactly like that. The PC had been sitting
in storage, on the main floor of my house (i.e. dry
and warm), and the Antec caps started to leak while
it was just sitting there. And I got a puff of gray
smoke when I fired it up again. The capacitors
on the motherboard, can also have domed lids and
orange dried deposits on top. And that's mainly
what a visual inspection covers. Only about 10%
of potential faults are covered by a visual inspection,
so it's not a "heroic method" by any stretch of
the imagination. But visual inspection is "free"

https://en.wikipedia.org/wiki/Capacitor_plague

Of my three failed ATX supplies here, only one
of them looks exactly like the Wikipedia article.

Paul

 

[Linea Recta]

"OG" <X@NOWHERE.COM> schreef in bericht
news:ngaobc$1mh4$1@adenine.netfront.net...

Quad Core Desktop Windows 7 PC been running for several days.
Today plug and unplugged USB drives to make a copy to USB Drive.

Started the copy and the screen went blank and the room filled with smoke.
Smelled like burning resistor (I think). I have smelled that smell
before.

Turned off the PC power.
Turned on the fans to get the smoke out.
Smoke detectors did not alert.

What are typical failures to look for?

Please give suggestions.
First I need to figure out how to get the cover off.

--- news://freenews.netfront.net/ - complaints: news@netfront.net ---

If you had copied by firewire I would have known the answer...



--


|\ /|
| \/ |@rk
\../
\/os

 

[Ian Field]

"philo" <philo@privacy.net> wrote in message
news:ngaoou$lgd$2@dont-email.me...

On 05/03/2016 12:49 PM, OG wrote:
Quad Core Desktop Windows 7 PC been running for several days.
Today plug and unplugged USB drives to make a copy to USB Drive.

Started the copy and the screen went blank and the room filled with
smoke. Smelled like burning resistor (I think). I have smelled that
smell before.

Turned off the PC power.
Turned on the fans to get the smoke out.
Smoke detectors did not alert.

What are typical failures to look for?

Please give suggestions.
First I need to figure out how to get the cover off.
X


When you open the case it will probably be obvious.

If you do not see any burned, it's probably the power supply.

I've seen a well cremated PFC inductor in a PSU.

Since the PFC is basically a flyback boost converter, I just removed the
MOSFET and linked out the inductor.

Some PSUs have a dirty great iron cored choke in series with the mains input
for PFC - those are probably less likely to self incinerate.

Venting electrolytics can lay smoke like a Royal navy destroyer - but it
usually doesn't smell like burning resistors.

 

[Ian Field]

"philo" <philo@privacy.net> wrote in message
news:ngarce$1c0$2@dont-email.me...

On 05/03/2016 01:43 PM, OG wrote:
There a sound level detectors for locating sound.
There are infrared detectors for location heat.
There are volt meters for detecting voltages.
There are scopes for detecting waveforms.

Are there smell detectors for locating burned components?





Yes. Your eyes

Fry used Professor Farnsworth's smelloscope to locate Uranus.

 

[Ian Field]

"MJC" <gravity@mjcoon.plus.com> wrote in message
news:MPG.31930409e53b75bd1c@news.plus.net...

In article <ngarhd$141a$1@gioia.aioe.org>, AIEO@AIOESPAM.COM says...

There a sound level detectors for locating sound.
There are infrared detectors for location heat.
There are volt meters for detecting voltages.
There are scopes for detecting waveforms.

Are there smell detectors for locating burned components?

Not sure whether you'd want a dog or a canary!

Don't feed the dog liver & onion gravy if you're trying to isolate a
smell............

 

[Michael Black]

On Tue, 3 May 2016, philo wrote:

On 05/03/2016 01:43 PM, OG wrote:
There a sound level detectors for locating sound.
There are infrared detectors for location heat.
There are volt meters for detecting voltages.
There are scopes for detecting waveforms.

Are there smell detectors for locating burned components?





Yes. Your eyes

I thought it was your nose.

Michael

 

[Clifford Heath]

On 04/05/16 07:57, Jeff Liebermann wrote:

On Tue, 3 May 2016 11:43:52 -0700, OG <AIEO@AIOESPAM.COM> wrote:

There a sound level detectors for locating sound.
There are infrared detectors for location heat.
There are volt meters for detecting voltages.
There are scopes for detecting waveforms.

Are there smell detectors for locating burned components?

Yes. I had the displeasure of locating the source of a burning smell
among a collection of immovable servers in a server farm. To make
matters worse, there was lots of cooling air flow to disperse the
smell. If there was any smoke, I couldn't see it.
So, I stuck a clear vinyl hose in my nose, and waved the other end of
the hose around

A vinyl tube in the ear is the best way of locating strange noises in
your car's engine bay too.

 

[Jeff Liebermann]

On Tue, 3 May 2016 11:43:52 -0700, OG <AIEO@AIOESPAM.COM> wrote:

There a sound level detectors for locating sound.
There are infrared detectors for location heat.
There are volt meters for detecting voltages.
There are scopes for detecting waveforms.

Are there smell detectors for locating burned components?

Yes. I had the displeasure of locating the source of a burning smell
among a collection of immovable servers in a server farm. To make
matters worse, there was lots of cooling air flow to disperse the
smell. If there was any smoke, I couldn't see it.

So, I stuck a clear vinyl hose in my nose, and waved the other end of
the hose around the fan exit ports on the servers. That isolated the
smell to one server. I got permission to shut it down. However, when
I opened the case, I couldn't see anything obviously burning. So, I
did the vinyl hose trick again, and eventually isolated the smoke to
the power supply. I didn't want to do component level troubleshooting
so I just replaced the power supply.

Somewhat later, I bought am "air quality monitor".
<http://802.11junk.com/jeffl/crud/Nikken-AQM.jpg>
It's quite sensitive and will easily detect the smoke from a burning
component. That came in handy when I noticed that something smelled
like it was burning in my palatial office. I waved it around to sniff
the various likely culprits and eventually isolated the smoke to the
APC BackUPS XS-1000 in the photo. Notice the bar graph showing tilt.

Here's what's inside the Nikken AQM:
<http://802.11junk.com/jeffl/Nikken%201394%20Air%20Quality%20Monitor/>
Inside IR dust scattering sensor:
<http://802.11junk.com/jeffl/Nikken%201394%20Air%20Quality%20Monitor/Nikken-AQM-08.jpg>


--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Jeff Liebermann]

On Tue, 3 May 2016 16:27:37 -0400, Michael Black <et472@ncf.ca> wrote:

On Tue, 3 May 2016, philo wrote:
Yes. Your eyes

I thought it was your nose.
Michael

If your nose runs, and your feet smell, you're built upside down.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[MJC]

In article <alpine.LNX.2.02.1605031627260.17851@darkstar.example.org>,
et472@ncf.ca says...

On Tue, 3 May 2016, philo wrote:

On 05/03/2016 01:43 PM, OG wrote:
There a sound level detectors for locating sound.
There are infrared detectors for location heat.
There are volt meters for detecting voltages.
There are scopes for detecting waveforms.

Are there smell detectors for locating burned components?





Yes. Your eyes

I thought it was your nose.

Michael

Years ago a colleague had a pimple on the end of his nose which he
claimed made it much more sensitive and discriminating for detecting
overheated components...

Mike.