Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems.

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
Posted to sci.electronics.repair,alt.windows7.general
external usenet poster
 
Posts: 1
Default PC Smoke Chapter 2

So, after the long discussion on smoke detectors I thought it best to
start a new post hole.

I opened the case and looked at the board.
It is a so called military grade MSI ATX motherboard.
I saw no charred anything.
But I did see pieces of charred something sitting on the board and
looked upwards and discovered a cable hanging loose.

Look closely at the end of the cable and saw what was left of a drive
power connector. Traced that to the power input to a Hitachi 2T HDD.

What that my C: drive (Win 7) ? Yikes!
I have four 2T drives in there.
Thank goodness I just backed up the C: drive using Macrium Reflect Free
to an external USB Drive.

Anyway, now I am wondering if the power supply was taken out.
It is a 600W CoolerMaster RS-500-PCAR.
Do these protect themselves or just melt down with the connector.
The cabling is hard ot get to since the PC is packed tight with 4 HHD
and two DVDs and a few boards plugged into the motherboard.

So maybe the connector contact was not so good and the resistance
increased to a point where the connector melted the shorted out?
The connector was melted AND also turned to dust.

Connector went bad or ?

Wonder if the drive is still good.
Got to take it out and have a good look.

Thoughts (other than smoke detectors).

--- news://freenews.netfront.net/ - complaints: ---
  #2   Report Post  
Posted to sci.electronics.repair,alt.windows7.general
external usenet poster
 
Posts: 61
Default PC Smoke Chapter 2

OG wrote:
So, after the long discussion on smoke detectors I thought it best to
start a new post hole.

I opened the case and looked at the board.
It is a so called military grade MSI ATX motherboard.
I saw no charred anything.
But I did see pieces of charred something sitting on the board and
looked upwards and discovered a cable hanging loose.

Look closely at the end of the cable and saw what was left of a drive
power connector. Traced that to the power input to a Hitachi 2T HDD.

What that my C: drive (Win 7) ? Yikes!
I have four 2T drives in there.
Thank goodness I just backed up the C: drive using Macrium Reflect Free
to an external USB Drive.

Anyway, now I am wondering if the power supply was taken out.
It is a 600W CoolerMaster RS-500-PCAR.
Do these protect themselves or just melt down with the connector.
The cabling is hard ot get to since the PC is packed tight with 4 HHD
and two DVDs and a few boards plugged into the motherboard.

So maybe the connector contact was not so good and the resistance
increased to a point where the connector melted the shorted out?
The connector was melted AND also turned to dust.

Connector went bad or ?

Wonder if the drive is still good.
Got to take it out and have a good look.

Thoughts (other than smoke detectors).


I would not trust the connectors now.

That means replacing the power supply.

If, on the other hand, the connector was a SATA Y-cable
or a SATA extension, maybe that was the defective part,
and the power supply doesn't have a quality issue.

If the power supply connector end burned, you cannot
use that drive again. The contacts on the drive end,
will be heat-damaged and degraded, and will encourage
the connector on a new supply, to fail in exactly the
same way. You may be able to connect the drive long
enough to clone it, but I would no longer trust it.

When the connector is new, the metal is nice and shiny
and conductive. After an overheat issue, the metal
is oxidized, heat stressed, and has a higher resistance.
Replacing both ends of the connector system, is required
to return things to mint condition. And that's why you
shouldn't use that hard drive again.

If you do want to use the hard drive again, you can use
an extension cord. When it burns the extension cord,
there would be no damage to the new power supply.

PSU ----- Molex to SATA ----
---- - - - Bad drive

^
|
+--- Will burn here...

So if it were to burn again, just the middle
(extension cable) would need to be replaced.
It all depends on whether you like the smell
of "resistor smoke", as to whether that is
a practical alternative (isolates the damage
a bit better). The second time it fails,
will be for potentially different reasons
than the first time, due to the heat
damage to the drive end power contacts.

You can easily solder a pigtail to the hard drive,
to power it in place of the SATA 15 pin. So even if
you didn't have backups, you may be able to get
the data off it. It would require locating where
+5V, +12V, GND, GND are on the controller board,
to tap in and connect a Molex pig tail as a replacement.
I did that to replace a burned end connector on a
video card and it held up fine.

*******

One suggestion here is "tin whiskers". A metallurgy
problem. You cannot use pure tin on assemblies,
because a thin spike of material will "grow" between
conductors. The whisker grows between conductors,
until it shorts them out.

https://community.spiceworks.com/top...lted-smell-bad

We had some special RAM modules we designed at work.
The first ones, were made with gold all over the place.
At the time, gold wasn't nearly as expensive as it is
now. Anyway, in the spirit of cost-reduction, the
next generation (same form factor), they decided
it would be fun to make them with tin in place of the
gold. And apparently, the person who did that, had never
heard of tin whiskers. And pretty well exactly one year
to the day, each module would fail, as a whisker would
grow across the surface of the substrate. We used to
run an Xacto knife between tracks, to cut the
whiskers, but they would only grow back again. Making
the RAM modules a write-off. The substrate in this case
was ceramic, so these were not even remotely close
to modern DIMMs or SIMMs in design. A thorough
understanding of metallurgy is required for
anyone doing this sort of design work (i.e. don't
ask me to do it :-) )

Metallurgy affects lots of stuff. When you see electrical
contacts on things, they consist of a number of layers
of plating. The materials and order of layering is
determined by safe metallurgy. So you could use tin,
if it was combined with the correct other materials.
So someone knows what metal mixture, plate up, or whatever,
will stop whiskers. There's no need for whiskers in
electronics in 2016. This is "all known stuff". You
shouldn't be designing connectors and cables, unless
you know this stuff.

Paul
  #3   Report Post  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 420
Default PC Smoke Chapter 2

What Paul says (+1)
  #4   Report Post  
Posted to sci.electronics.repair,alt.windows7.general
external usenet poster
 
Posts: 47
Default PC Smoke Chapter 2

OG wrote:

Anyway, now I am wondering if the power supply was taken out.
It is a 600W CoolerMaster RS-500-PCAR.
Do these protect themselves or just melt down with the connector.
The cabling is hard ot get to since the PC is packed tight with 4 HHD and two DVDs and a
few boards plugged into the motherboard.


IMO, 600w and cooling is not nearly enough for what you have that machine doing.
This machine has a 750w p/s and sometimes it gets stressed.
2-4 hdds, 1-2 dvds, various cards, etc.
cpu fan, hdd fan, 2 bridge fans, ram fan, pwr sup fan, gpu fan, all set to max.
Everything overclocked. 24" floor fan on the side of the case.
When the current p/s goes bad I'll get a 1 kw p/s.

  #5   Report Post  
Posted to sci.electronics.repair,alt.windows7.general
external usenet poster
 
Posts: 2,399
Default PC Smoke Chapter 2

On 05/06/2016 08:52 PM, Paul in Houston TX wrote:
OG wrote:

Anyway, now I am wondering if the power supply was taken out.
It is a 600W CoolerMaster RS-500-PCAR.
Do these protect themselves or just melt down with the connector.
The cabling is hard ot get to since the PC is packed tight with 4 HHD
and two DVDs and a
few boards plugged into the motherboard.


IMO, 600w and cooling is not nearly enough for what you have that
machine doing.
This machine has a 750w p/s and sometimes it gets stressed.
2-4 hdds, 1-2 dvds, various cards, etc.
cpu fan, hdd fan, 2 bridge fans, ram fan, pwr sup fan, gpu fan, all set
to max.
Everything overclocked. 24" floor fan on the side of the case.
When the current p/s goes bad I'll get a 1 kw p/s.



The total power of the supply is irrelevant as to the connector that
burned. The supply only delivers what is called for.

More than likely the connector was not pushed in all the way, when the
drive was installed.

Otherwise it was loose pins


  #6   Report Post  
Posted to sci.electronics.repair,alt.windows7.general
external usenet poster
 
Posts: 47
Default PC Smoke Chapter 2

philo wrote:
On 05/06/2016 08:52 PM, Paul in Houston TX wrote:
OG wrote:

Anyway, now I am wondering if the power supply was taken out.
It is a 600W CoolerMaster RS-500-PCAR.
Do these protect themselves or just melt down with the connector.
The cabling is hard ot get to since the PC is packed tight with 4 HHD
and two DVDs and a
few boards plugged into the motherboard.


IMO, 600w and cooling is not nearly enough for what you have that
machine doing.
This machine has a 750w p/s and sometimes it gets stressed.
2-4 hdds, 1-2 dvds, various cards, etc.
cpu fan, hdd fan, 2 bridge fans, ram fan, pwr sup fan, gpu fan, all set
to max.
Everything overclocked. 24" floor fan on the side of the case.
When the current p/s goes bad I'll get a 1 kw p/s.



The total power of the supply is irrelevant as to the connector that burned. The supply
only delivers what is called for.

More than likely the connector was not pushed in all the way, when the drive was installed.

Otherwise it was loose pins


Yea, I agree. Should have made that clear in my post.
  #7   Report Post  
Posted to sci.electronics.repair,alt.windows7.general
external usenet poster
 
Posts: 2,399
Default PC Smoke Chapter 2

On 05/06/2016 10:48 PM, Paul in Houston TX wrote:
philo wrote:
On 0

The total power of the supply is irrelevant as to the connector that
burned. The supply
only delivers what is called for.

More than likely the connector was not pushed in all the way, when the
drive was installed.

Otherwise it was loose pins


Yea, I agree. Should have made that clear in my post.




At any rate, thought I've seen burned or over-heated connections, I've
never seen one go up in smoke.
  #8   Report Post  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 1,384
Default PC Smoke Chapter 2

philo wrote:

On 05/06/2016 10:48 PM, Paul in Houston TX wrote:
philo wrote:
On 0

The total power of the supply is irrelevant as to the connector that
burned. The supply
only delivers what is called for.

More than likely the connector was not pushed in all the way, when the
drive was installed.

Otherwise it was loose pins


Yea, I agree. Should have made that clear in my post.




At any rate, thought I've seen burned or over-heated connections, I've
never seen one go up in smoke.

Another possibility is that the drive developed an internal short (maybe
blown power fet in the motor drive) and started drawing huge currents. The
connector ended up being the weakest link and burned up.

That is one of the dangers of putting insanely overpowered supplies in PCs.
Some people have 700+ W supplies in ordinary desktop systems that typically
draw less than 150 W. This is mostly due to sellers making a lot of money
over-selling stuff to people who don't know better.

Jon

Jon
  #9   Report Post  
Posted to sci.electronics.repair,alt.windows7.general
external usenet poster
 
Posts: 18
Default PC Smoke Chapter 2

I have more then once a shorted USB connector is worse


--
AL'S COMPUTERS
"philo" wrote in message
...
On 05/06/2016 10:48 PM, Paul in Houston TX wrote:
philo wrote:
On 0

The total power of the supply is irrelevant as to the connector that
burned. The supply
only delivers what is called for.

More than likely the connector was not pushed in all the way, when the
drive was installed.

Otherwise it was loose pins


Yea, I agree. Should have made that clear in my post.




At any rate, thought I've seen burned or over-heated connections, I've
never seen one go up in smoke.



  #10   Report Post  
Posted to sci.electronics.repair,alt.windows7.general
external usenet poster
 
Posts: 1
Default PC Smoke Chapter 2

Upon further examination it looks like the connector may have wiggled loose.
Why, because the gold connector pads on the HDD were melted off only
near the edge of the connector. Little damage to the PWB of the HDD. I
see no damage to the gold from that damaged area into the HDD.

A short occurred between the 12v Yellow and GND Black power feed.
The connector evaporated there (ash and chunks all over) and the wires
evaporated back from where the connector was by over an inch. Yes, over
an inch of yellow and black (adjacent) wire evaporated. Must have been
exciting to see the arc.

So probably the arc started, the connector evaporated and came off the
HDD, the arc continued and ate the wires until the PS gave its all then
had enough.

So the smoke was a combination of gold, connector plastic, copper PWB
trace, copper wire, vinyl wire covering and whatever else was in the mix.
Thankfully I did not get to breath much since the whole house fan and
computer room fan were immediately turned on and evacuated the
"computer" room quickly.

Got a new PS and HDD ready to install.
Will take baby steps putting it all together.
The new EVGA PS is much higher efficiency than the last.
The new HDD is a WD "Black".


--- news://freenews.netfront.net/ - complaints: ---
Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
CHAPTER 13 BANKRUPTCY KANMANI Electronics Repair 0 June 11th 08 05:39 AM
A baby barn: chapter II C & S Woodworking Plans and Photos 0 April 26th 07 02:56 AM
A baby barn: chapter II C & S Woodworking Plans and Photos 0 April 26th 07 02:56 AM
Chapter 13 Buyout Ch13Buyout.com Home Ownership 0 September 30th 06 11:19 AM
Smoke alarms for rooms where people smoke [email protected] UK diy 26 January 10th 05 05:54 PM


All times are GMT +1. The time now is 07:27 PM.

Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 DIYbanter.
The comments are property of their posters.
 

About Us

"It's about DIY & home improvement"