Capacitor leakage anyone?

  • Thread starter Thread starter Hrvoje Èièak
  • Start date Start date
H

Hrvoje Èièak

Hi all!

My 18 months old Epox 4PEA+ motherboard just went berserk yesterday. After
opening the chassis I spotted that capacitors near AGP port, SIL SATA
controller and TI firewire controller are somewhat inflated and that they
have some kind of yellow crust. I've heard of capacitors with low quality
electrolyte made by some Taiwan company that went in mass production, but
didn't think that a near $200 motherboard would have these installed.
Furthermore all of damaged capacitors are small greenish ones with a three
point star engraved on upper surface. On the other hand those black with
sliver stripe and letter "K" engraved on their surface look like they just
left production plant. Anyone else having the same problem?
 
Hrvoje said:
My 18 months old Epox 4PEA+ motherboard just went berserk
yesterday.
I spotted that capacitors near AGP port, SIL SATA controller
and TI firewire controller are somewhat inflated and that
they have some kind of yellow crust. I've heard of capacitors
with low quality electrolyte made by some Taiwan company that
went in mass production, but didn't think that a near $200
motherboard would have these installed. Furthermore all of
damaged capacitors are small greenish ones with a three
point star engraved on upper surface. On the other hand those
black with sliver stripe and letter "K" engraved on their
surface look like they just left production plant.
Click to expand...

See www.badcaps.net for the story. Several Taiwan companies were
involved, not just one, but they all bought their capacitor chemicals
from a single source that produced a badly counterfeited a Japanese
chemical package. All of those capacitors were the low ESR (effective
series resistance) type, typically used for filtering highly pulsating
DC into smooth DC, such as for voltage regulators found on
motherboards. Other electrolytic capacitors aren't low ESR and are
used only for bypass, that is they're fed DC and are meant to keep that
DC clean when chips require sudden bursts of power. The only solution
to the bad caps is replacement, which isn't difficult but requires a
powerful soldering iron (40-50 watts) and Japanese brand capacitors
(Panasonic/Matsushita, Sanyo, Nichicon, United Chemicon, Rubycon).
 
My 18 months old Epox 4PEA+ motherboard just went berserk
yesterday.
I spotted that capacitors near AGP port, SIL SATA controller
and TI firewire controller are somewhat inflated and that
they have some kind of yellow crust. I've heard of capacitors
with low quality electrolyte made by some Taiwan company that
went in mass production, but didn't think that a near $200
motherboard would have these installed. Furthermore all of
damaged capacitors are small greenish ones with a three
point star engraved on upper surface. On the other hand those
black with sliver stripe and letter "K" engraved on their
surface look like they just left production plant.
Click to expand...

See www.badcaps.net for the story. Several Taiwan companies were
involved, not just one, but they all bought their capacitor chemicals
from a single source that produced a badly counterfeited a Japanese
chemical package. All of those capacitors were the low ESR (effective
series resistance) type, typically used for filtering highly pulsating
DC into smooth DC, such as for voltage regulators found on
motherboards. Other electrolytic capacitors aren't low ESR and are
used only for bypass, that is they're fed DC and are meant to keep that
DC clean when chips require sudden bursts of power. The only solution
to the bad caps is replacement, which isn't difficult but requires a
powerful soldering iron (40-50 watts) and Japanese brand capacitors
(Panasonic/Matsushita, Sanyo, Nichicon, United Chemicon, Rubycon).


Thanx for the info... I don't see myself as an experienced electronics
tehnician bold einough to do some soldering on MB, but will try to find one,
'cause I really like this motherboard, and I would like to see it repaired.

Hrvoje
 
Hrvoje said:
Hi all!

My 18 months old Epox 4PEA+ motherboard just went berserk yesterday. After
opening the chassis I spotted that capacitors near AGP port, SIL SATA
controller and TI firewire controller are somewhat inflated and that they
have some kind of yellow crust.
Click to expand...

That's an amazingly common problem nowadays. I'm starting to wonder if
it's "planned obsolesence"

I had a similar problem with a year-old Epox board, recently, but it's
not just Epox.
 
On Wed, 08 Jun 2005 12:06:07 -0400, Bob Horvath wrote:

HI all,
I had a FIC board go out with the capacitor issue a few months
ago.
Bob
 
I didn't look at the badcaps.net site until after I sent the previous post.
It looks like they do repair too.
 
Hrvoje said:
Thanx for the info... I don't see myself as an experienced
electronics tehnician bold einough to do some soldering on
MB, but will try to find one, 'cause I really like this
motherboard, and I would like to see it repaired.
Click to expand...

Don't let the typical computer technician repair it because few of them
know how to solder (my apologies to those of you who do), but most TV
and audio repair shops should. Insist they use capacitors rated not
only for 105 Celcius but also for low ESR because not all 105C caps are
low ESR. www.digikey.com, www.mouser.com, and www.bdent.com sell
appropriate caps. Replace not only bulging or leaking one but also any
with colors and markings similar to them since they're likely marginal
as well. The caps most likely affected are typically surrounding the
CPU and any donut-shaped coils.

If you attempt the job yourself, get a 40 watt or higher soldering iron
(not gun) and practice desoldering some old, unneeded 4-6 layer circuit
boards (not 1-2-layer -- unrealistically easy). The safest way to
remove a capacitor without special tools is by cutting them off on top
with wire cutters so each wire lead can be unsoldered and pulled out
individually. This may seem drastic but is actually gentler than most
other methods, especially removing solder with a suction bulb (tiny
turkey baster). The next safest method is using narrow (2mm) copper
desoldering braid, but it needs plenty of heat, so wipe off and tin the
soldering iron tip frequently, and cut off any used braid before
desoldering the next lead. Wiggle each wire lead side to side to crack
off any remaining solder before pulling it out, but if it doesn't crack
apply fresh 60-63% tin solder and start all over. It's not unusual to
consume 1" of desoldering braid per wire lead.
 
soyo here , and many

Bob Horvath said:
On Wed, 08 Jun 2005 12:06:07 -0400, Bob Horvath wrote:

HI all,
I had a FIC board go out with the capacitor issue a few months
ago.
Bob
Click to expand...
 
Hrvoje Cicak wrote:




Don't let the typical computer technician repair it because few of them
know how to solder (my apologies to those of you who do), but most TV
and audio repair shops should. Insist they use capacitors rated not
only for 105 Celcius but also for low ESR because not all 105C caps are
low ESR. www.digikey.com, www.mouser.com, and www.bdent.com sell
appropriate caps. Replace not only bulging or leaking one but also any
with colors and markings similar to them since they're likely marginal
as well. The caps most likely affected are typically surrounding the
CPU and any donut-shaped coils.

If you attempt the job yourself, get a 40 watt or higher soldering iron
(not gun) and practice desoldering some old, unneeded 4-6 layer circuit
boards (not 1-2-layer -- unrealistically easy). The safest way to
remove a capacitor without special tools is by cutting them off on top
with wire cutters so each wire lead can be unsoldered and pulled out
individually. This may seem drastic but is actually gentler than most
other methods, especially removing solder with a suction bulb (tiny
turkey baster). The next safest method is using narrow (2mm) copper
desoldering braid, but it needs plenty of heat, so wipe off and tin the
soldering iron tip frequently, and cut off any used braid before
desoldering the next lead. Wiggle each wire lead side to side to crack
off any remaining solder before pulling it out, but if it doesn't crack
apply fresh 60-63% tin solder and start all over. It's not unusual to
consume 1" of desoldering braid per wire lead.
Click to expand...

The two biggest things to watch out for is overheating, causing traces to
peel up, and pulling the feedthrough out along with the lead.

The cap is bad to begin with so I rock the can till the leads break loose
inside and then pull the can off, leaving the leads in the board. That then
give access to one lead at a time to heat and pull, with a nice piece to
get the needle nose on.
 
You'll ruin that multilayer mobo trying to resolder those
caps. If that thing is out of warranty, I'd toss it and get
another brand. If not, RMA it. Plus, I kind of suspect
that you have a voltage reg blown, and that is what took
out the caps. It may have been the psupply that took out
the Vreg ... or it may have been just heat in the case,
but it would have been around 95 F to do that. If the
box was in sunlight, and turned off, that would do it.

johns
 
I am an etech. You can' t go on a multilayer mobo with
a soldering iron ... at all. I have a rework station that
evenly heats all the leads at the same time to exactly the
right temp. That is what it takes, and it works about
half the time.

johns
 
johns said:
You'll ruin that multilayer mobo trying to resolder those
caps. If that thing is out of warranty, I'd toss it and get
another brand. If not, RMA it. Plus, I kind of suspect
that you have a voltage reg blown, and that is what took
out the caps. It may have been the psupply that took out
the Vreg ... or it may have been just heat in the case,
but it would have been around 95 F to do that. If the
box was in sunlight, and turned off, that would do it.

johns
Click to expand...

If it's out of warranty, and he's just gonna chuck it, he has nothing to
lose.

MC
 
See www.badcaps.net for the story. Several Taiwan companies were
involved, not just one, but they all bought their capacitor chemicals
from a single source that produced a badly counterfeited a Japanese
chemical package.
Click to expand...

Yes but that was far longer than 18 months ago. That can't be the same
problem.
 
johns said:
You'll ruin that multilayer mobo trying to resolder those
caps. If that thing is out of warranty, I'd toss it and get
another brand.
Click to expand...

Now why the hell would you toss for fear of possibly ruining it? I soldered
new capacitors on my motherboard to save money and it worked just fine.
Paying someone to do it was going to cost as much as replacing the
motherboard. Point being not that it's foolproof, but it obviously works
sometimes.
 
jeffc said:
Yes but that was far longer than 18 months ago. That can't be the same
problem.
Click to expand...

I belive that it is the same problem since board was build around same time
that happened. I just recived it 18 months ago.

Pozdrav, Hrvoje
 
johns said:
You'll ruin that multilayer mobo trying to resolder those
caps. If that thing is out of warranty, I'd toss it and get
another brand. If not, RMA it. Plus, I kind of suspect
that you have a voltage reg blown, and that is what took
out the caps. It may have been the psupply that took out
the Vreg ... or it may have been just heat in the case,
but it would have been around 95 F to do that. If the
box was in sunlight, and turned off, that would do it.

johns
Click to expand...

If that happened I'd expect to see capacitors near CPU slot inflated... but
they are all normal. As I said in original post these capacitors are near
secondary controllers (SATA and FireWire) and AGP. Those that take care of
processor voltage (most commonly damaged) looks OK. Plus, I've had mobo with
vreg blown away, and you could see the damage - there was a hole on one of
"block resistors" (I don't know right English phrasing for that part).
Bottom line is that I belive that circuitry on this mobo is still in working
state, and that only capacitors are ruined... and I've seen quite a few
malfunctioning boards.
As for multilayer design. I too fear that "fixing" mobo with soldering iron
would actually ruin MB, but I ran out of solutions because similar mobo
can't be purchuased in Croatia, and I do need additional PATA and SATA
controller this MB have.

Pozdrav, Hrvoje
 
johns said:
I am an etech. You can' t go on a multilayer mobo with
a soldering iron ... at all. I have a rework station that
evenly heats all the leads at the same time to exactly the
right temp. That is what it takes, and it works about
half the time.
Click to expand...

If you're careful and use a temp controlled iron with
a fine tip you can easily replace capacitors, or any
through-hole components. Chips and micro SMDs are
another matter however.

I heat one side and tilt the cap away from the side I
just heated so that lead comes out a little. I then
swap to the other lead and work the capacitor out
little by little. Once I have a little space I snip
one lead allowing the cap to be removed when the
uncut lead is heated. I then use tweezers to remove
cut lead while heating it. You might need to add a
little solder to the pads initially to help transfer
heat into the joint so it melts properly.

I have a vaccum desolder gun which I use to clean out
the holes before fiting a new capacitor. Apparently
de-solder wick also works to clean up the holes. I
also have a jewelers magnifying lens which comes in
handy for inspecting the hole to make sure you haven't
damaged it.

Pop in the new capacitor and use just the right amount
of solder, snip the excess leads and you are good to go.

What ever you do don't attack a PCB with a soldering
iron more suited to plumbing that electronic work.

Plan ahead, don't apply heat for too long, once the
solder melts do the work and remove the iron quickly.
If you keep the joint heated while you are thinking
what to do you are likely to lift the copper traces
off of the board. Plan to spend 15 minutes per
capacitor until you get the hang of it.

I did my ABit KT133 RAID board over 2 afternoons as
it was too much for a single stretch.
 
Homie is a good dude. you can trust him as he has been in the business
for
a while
Click to expand...

I've searched his homepage for info but couldn't find anywhere does he
accepts mobos outside of US (I'm from Europe). Thank you for info, I'll
contact him via e-mail.

Pozdrav, Hrvoje
 
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