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From: kronflux on 9 Dec 2009 04:32
okay, the subject is a little off, I -know- I should be worried.
here's the scoop.
basically I have an old pc, celeron or something here, which I was
using as a media PC, to watch my downloaded movies on my tv, with s-
video out and such.
anyway.
since around when I put it together, I was getting little shocks
occasionally from it. I don't know what it could be. every time it
happened, I got the shock from the case itself. and each time I
quickly unplugged the computer. once plugged back in, it didn't have
any problems.
recently I haven't been getting shocks at all, but just yesterday I
turned it on, and it was running for a while just idle, and I smelled
burning, and then it froze. I quickly rushed over and unplugged it,
and looked inside, and to my surprise there was a component on the
motherboard that was glowing red hot. I don't know what the component
is called, but here's a link to a picture of it, then a picture of the
motherboard to show reference as to where it is.
first I'd like to point out, part of my problem is likely dust and
dirt. but we'll get to that.
http://bayimg.com/image/bagagaaco.jpg
http://bayimg.com/image/fagakaaco.jpg

as I said, this component was glowing red hot. but! the computer turns
on just fine even now. it boots and everything.
aside from dust, what might have caused this, and should I be
concerned, once I clean it?
From: Geoffrey S. Mendelson on 9 Dec 2009 05:14
kronflux wrote:
> basically I have an old pc, celeron or something here, which I was
> using as a media PC, to watch my downloaded movies on my tv, with s-
> video out and such.
> anyway.
> aside from dust, what might have caused this, and should I be
> concerned, once I clean it?

Just buy a new PC. You'll be much happier in the end. Here you can get a
dual core ATOM processor (very low power), 1g RAM, 256G HD and a DVD drive
for $260 (including 16.5% VAT).

You may have to shop around for one with an S-Video out, but if you are
buying an LCD TV in the near future, just get one with a compatible
(to the new motherboard) video connection.

Geoff.

--
Geoffrey S. Mendelson, Jerusalem, Israel gsm(a)mendelson.com N3OWJ/4X1GM
From: Samuel M. Goldwasser on 9 Dec 2009 09:00
kronflux <kronflux(a)gmail.com> writes:

> okay, the subject is a little off, I -know- I should be worried.
> here's the scoop.
> basically I have an old pc, celeron or something here, which I was
> using as a media PC, to watch my downloaded movies on my tv, with s-
> video out and such.
> anyway.
> since around when I put it together, I was getting little shocks
> occasionally from it. I don't know what it could be. every time it
> happened, I got the shock from the case itself. and each time I
> quickly unplugged the computer. once plugged back in, it didn't have
> any problems.
> recently I haven't been getting shocks at all, but just yesterday I
> turned it on, and it was running for a while just idle, and I smelled
> burning, and then it froze. I quickly rushed over and unplugged it,
> and looked inside, and to my surprise there was a component on the
> motherboard that was glowing red hot. I don't know what the component
> is called, but here's a link to a picture of it, then a picture of the
> motherboard to show reference as to where it is.
> first I'd like to point out, part of my problem is likely dust and
> dirt. but we'll get to that.
> http://bayimg.com/image/bagagaaco.jpg
> http://bayimg.com/image/fagakaaco.jpg
>
> as I said, this component was glowing red hot. but! the computer turns
> on just fine even now. it boots and everything.
> aside from dust, what might have caused this, and should I be
> concerned, once I clean it?

Unsolder and remove that part - it's a bypass capacitor - and see if the PC
runs. It's possible it just went bad. If the PC runs OK, it will be fine
without it. If not, probably time to get a new PC as someone else suggested.

The shocks are a totally different problem.

Is the PC plugged into a PROPERLY grounded outlet? If not, then the case
can have some voltage on it from the power supply RFI/line filters. PCs
should always be plugged into grounded outlets for your safety and also
reliability. It's also possible there is a fault in the power supply which
would blow the line fuse if the case were properly grounded. And that can
be very dangerous (but also relatively unlikely).

The other possibility is that it is simply very dry there and you're getting
static shocks like walking across a carpet and touching a doorknob.

A third possibility is that some other piece of equipment is faulty and
you're getting shocked when you touch that and the PC at the same time.

--
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Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
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From: William R. Walsh on 9 Dec 2009 10:13
Hi!

> since around when I put it together, I was getting little shocks
> occasionally from it.

Could have been nothing more than static electricity dissipating from
your body. If you touched a properly grounded electrically conductive
object, the result is to be expected. This is the right time of the
year for those where cold and dry winter weather has now arrived.

Unfortunately, this means I'm spending a lot of time in my carpeted
computer room getting a surprise each time I head across the carpet.
(My computer service room has a grounded workbench and no carpet, so
I'm thinking of moving into that room temporarily.)

> and to my surprise there was a component on the
> motherboard that was glowing red hot.

This cannot be good. Even if the board continued to work, I wouldn't
leave it running unattended for any reason. It could start a fire,
especially if the case is dusty.

However, since the board continues to operate, it seems to me like the
fault actually happened somewhere else. Since I can't presently see
the picture you linked to, I can't say for certain what circuit might
be affected.

Had the fault been on the motherboard, I'd have expected traces
leading to the component (or other, related traces) to have vaporized
shortly after the part you saw turned red hot.

Clean the machine. Keep an eye on it. And try running it with only a
monitor, mouse and keyboard in another location. Look at the
electrical service in the location where you've been running it to
make sure that everything is wired properly, and that all of your
entertainment devices are working correctly.

William
From: kronflux on 9 Dec 2009 12:32
well, the type of shock I was getting was a constant shock. not like a
zap-ish static kind of shock.
as I said, it hasn't happened lately, but I have tried the PC in
different locations, and it did the same, so it shouldn't be anything
to do with ground. I even tried different power cables.
I assume it's either the dust and dirt, the case sucks, or a faulty
power supply.

unfortunately buying a new PC is out of the question at the moment,
financially. which is why I use an old junker for a media PC.
there aren't really any special devices hooked up to it. it's got a
video card, network card, and a USB infrared remote receiver. the
video card gets an s-video out, which is adapted to a composite, and
that hooks up to my tv. the audio is onboard, which also hooks up to
my tv.

I think what I'll try is cleaning it first, and letting it run for a
while. watch it constantly, and see if it's still doing it. if not,
success. if it does, I may try unsoldering the bypass capacitor.
if it's a faulty bypass capacitor, should I replace this part, solder
a bridge between the two leads, or simply leave it empty?
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