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OG <X@NOWHERE.COM>: May 03 10:49AM -0700 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 <philo@privacy.net>: May 03 01:00PM -0500 On 05/03/2016 12:49 PM, OG wrote:   > 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 <spam@flippers.com>: May 03 11:02AM -0700 On 05/03/2016 10:49 AM, OG wrote:   > 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 <AIEO@AIOESPAM.COM>: May 03 11:43AM -0700 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 <philo@privacy.net>: May 03 01:44PM -0500 On 05/03/2016 01:43 PM, OG wrote:   > Are there smell detectors for locating burned components?   Yes. Your eyes :)

Mike Easter <MikeE@ster.invalid>: May 03 11:45AM -0700 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 <gravity@mjcoon.plus.com>: May 03 07:53PM +0100 In article <ngarhd$141a$1@gioia.aioe.org>, AIEO@AIOESPAM.COM says... > 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 <erratic@nomail.afraid.org>: May 03 03:06PM -0400 OG formulated the question :   > 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 <erratic@nomail.afraid.org>: May 03 03:09PM -0400 After serious thinking philo wrote :   > Yes. Your eyes :)   Exactly, look for smoke residue. This may be problematic if 'smoke filled the room' was not hyperbole.

"Mayayana" <mayayana@invalid.nospam>: May 03 03:10PM -0400 | 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 <nospam@needed.com>: May 03 03:33PM -0400 OG wrote:   > 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" <bleep.bleep@bleep.invalid>: May 03 09:42PM +0200 "OG" <X@NOWHERE.COM> schreef in bericht news:ngaobc$1mh4$1@adenine.netfront.net...   > 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" <gangprobing.alien@ntlworld.com>: May 03 09:09PM +0100 "philo" <philo@privacy.net> wrote in message news:ngaoou$lgd$2@dont-email.me... > 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" <gangprobing.alien@ntlworld.com>: May 03 09:11PM +0100 "philo" <philo@privacy.net> wrote in message news:ngarce$1c0$2@dont-email.me...   > Yes. Your eyes :)   Fry used Professor Farnsworth's smelloscope to locate Uranus.

"Ian Field" <gangprobing.alien@ntlworld.com>: May 03 09:13PM +0100 "MJC" <gravity@mjcoon.plus.com> wrote in message news:MPG.31930409e53b75bd1c@news.plus.net... >> 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 <et472@ncf.ca>: May 03 04:27PM -0400

Jeff Liebermann <jeffl@cruzio.com>: May 03 02:57PM -0700 >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 <jeffl@cruzio.com>: May 03 02:59PM -0700 >> 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 <gravity@mjcoon.plus.com>: May 03 11:39PM +0100 In article <alpine.LNX.2.02.1605031627260.17851@darkstar.example.org>, et472@ncf.ca says...   > > 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.

Clifford Heath <no.spam@please.net>: May 04 07:27AM +1000 On 04/05/16 07:57, Jeff Liebermann wrote: > 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.

Tekkie® <Tekkie@comcast.net>: May 03 04:17PM -0400 Danny DiAmico posted for all of us...     > new Whirlpool motor control board (PN 8540540), I'd appreciate > more advice now that it's pretty sure that it's the MCU and not > the CCU.   DOS Dead On Scene...   -- Tekkie

"Ian Field" <gangprobing.alien@ntlworld.com>: May 03 07:11PM +0100 "Ralph Mowery" <rmowery28146@earthlink.net> wrote in message news:MPG.31919968828164ed98969d@news.east.earthlink.net... > different brands. Sometimes even the same color wires were used.   > The Brand names are often sold and moved to a different country so the > quality may or may not be worse.   AFAIK: there's wheelers & dealers brokering brand names.   Bush wasn't the Rolls Royce of consumer electronics, but it was a well respected brand. Its now one of quite a few badges that get stuck on very cheap & very nasty Vestel equipment like the one I found.

"Ian Field" <gangprobing.alien@ntlworld.com>: May 03 07:24PM +0100 "N_Cook" <diverse@tcp.co.uk> wrote in message news:ngacfi$6b6$1@dont-email.me...   > 60/40 on lead free is dodgy, PbF is dodgey, PbF on PbF is dodgey, SAC on > PbF is dodgey, you do your own thing with fingers crossed and monitor for > bouncers over the next few years.   They do seem to be getting better at lead free - at one point, the bulk of TVs going to landfill increased five-fold because of dodgy soldering. They are gradually getting that figure down a bit.   Apart from the fact that manufacturing was taking lead out of the environment and binding into a relatively stable alloy - what difference is RoHS going to make with rain and hail lashed lead roofs running into the water table. There's been about 100 yrs of the landed gentry peppering agricultural land with lead shot. They're most unlikely to have got all the lead pipes that were used upto the 50s - in the UK; they're still discovering Roman lead water ducting.   The other side of the coin was lead in petrol - the petrochemical industry lead procurement was in tons, and the number had a lot of noughts on the end. That lead was being pumped in the air as particulates for us all to breathe.

KenO <kenitholson@yahoo.com>: May 03 10:07AM -0700 Recently removed 2 Digital MultiMeters from storage. When turned on after installing new 9V batteries both did not work.   Was guessing that the electrolytic capacitors need reforming so Googled and found "Reforming Electrolytic Capacitors" http://www.vcomp.co.uk/tech_tips/reform_caps.htm   Followed the instructions and one started working.   The other still shows the same 989 display (with changes of decimal point depending on the selector position.)   Have not yet taken it apart.   Can provide photos if someone wants.   It is same as "Brand New Digital Multimeter DM-1800" http://www.jlaforums.com/viewtopic.php?t=300532580   Appreciate any suggestions!!!   Thanks   Ken

N_Cook <diverse@tcp.co.uk>: May 03 07:07PM +0100 On 03/05/2016 18:07, KenO wrote:   > Appreciate any suggestions!!!   > Thanks   > Ken   Do they have rotary switch, function select ?

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