[ale] Pictures of the culprit (was OT: Diagnosing HW problem)

[James P. Kinney III]

WooHoo! Nice pics of dead hardware!

That stuff is power component devices. Likely a capacitor used to trim the
power to the CPU (they are often the largest things on the board).

If I recall, you had some power supply issues with this rig earlier. It is
likely that the PS was failing and cracked/nearly blew the case open on
the cap. The new PS is fine but the on-rush of current was the end of the
part.

The _bad_ news is you are likely not going to get a new mobo on a warranty
return. Unless the board was super expensive it's not worth a claim to
insurance.

As to tv tuner cable being the source of the power spike, Yes! It CAN happen.

My first system that I bought myself was toasted during a lightning strike
that was too close to the phone line. The box was OFF and UNPLUGGED but
the phone line to the modem was still in and the modem was serial port
cabled to the box. Chips were exploded in the modem, the mother board had
burn marks all over it between traces and the hard drive heads were welded
to the drive.

More recently, lightning hit a tree outside my office (~5' from where I
was standing!!). The EMP wave trashed all sorts of things. It induced a
high voltage on wires like the Cat5e all over the office. That destroyed
NICs and routers and switches and (I'm convinced but lacking direct
evidence) the untimely dead of motherboard and hard drive 2 days later.
I'll never forget seeing a pair of flourescent light tubes that were still
in the plastic wrap leaning against the wall lit up like they were running
at 500W instead of 35W! That was what let me figure out that the EMP
induced an electric field over 5kV! All of my surge protectors were
unphased. Even the first line of one shot wall wart protectors.

So a very nearby lightning show even with great surge protection can wreak
havoc.

> Guys,
>
> After examining the mb with a flashlight, I found the culprit.
>
> See:
>
> http://www.sourceillustrated.com/mb_1.jpg
> http://www.sourceillustrated.com/mb_2.jpg
>
> Ok...now for real technical lingo here...
>
> Of the four square thingies with the silver circle in the middle, notice
> one is most definitely *not* like the other.  First, what is this fried
> and charred thingie?  Second, does this look like it may have resulted
> from a lightning strike (we had some good ones here this weekend).  I have
> the box behind a good surge protector and UPS, but like a DAU I have cable
> running directly into a tv tuner card with no surge protection, so I'm
> wondering if that may have provided a clear path.
>
> Interested in learning your thoughts.  Thanks again for the help!
>
> John
>
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