HELP!! PC Posts (sometimes) then hangs with "static" sound...

[Ohaya]

Hi,

My daughter's PC wasn't able to boot this week, and she brought it home
this weekend for me to look at. It has an Abit KT7E motherboard, with a
Duron 850 CPU.

When she first told me about the problem, she said that it was making a
sound that sounded "like static".

Now that I have it here, I can confirm that description, and also I've
confirmed that the sound is coming from the PC speaker.

The machine will sometimes post, and I can get into BIOS. If I let it
sit there in BIOS, the display eventually goes blank, and the monitor
LED blinks yellow, indicating that it's lost video signal. When it does
that, I start hearing the "static" sound from the PC speaker.

Sometimes it won't post at all, just a blank screen and blinking monitor
LED and the static sound.

We've unplugged everything except the video card and 1 RAM stick. Still
the same symptoms.

We've pulled the motherboard to check for anything underneath, but found
nothing.

I've found this post:

http://groups.google.com/groups?hl=...-8&[email protected]

and I thought might be the CPU seating, so we've also pulled the CPU and
heatsink, and reseated that and put the heatsink back on with some new
paste. Still the same problem.

I did notice that there's a small fan on the motherboard itself,
probably for cooling the chipset, and sometimes doesn't turn when we
power the machine on. If I push the fan blades, it'll start turning,
but seems a little slow.

When in the BIOS, I've set it to "Safe Defaults", but still the same
thing.

When I can get into the BIOS, the BIOS PC Health display, it shows:

Core 1.63V
3.3V 3.41V
5V 4.85V
12V 12.00V

I'm thinking that it's either a problem with the motherboard or with the
power supply (the slow fan?)?

Any thoughts/suggestions on this?

A friend is going to try to bring over a spare power supply for me to
try this weekend, but, also, if it turns out to be the motherboard, can
anyone recommend a reliable replacement motherboard?

I went to a local Microcenter, and all of the motherboards they had only
supported DDR or DDR400, whereas she has 3 sticks of 256MB PC133 SDRAM,
so I'd like to reuse the RAM if we can.

Apologies for the long post, and thanks in advance!!

Jim

 

[ICee]

Hi,

My daughter's PC wasn't able to boot this week, and she brought it
home this weekend for me to look at. It has an Abit KT7E
motherboard, with a Duron 850 CPU.

When she first told me about the problem, she said that it was making
a sound that sounded "like static".

Now that I have it here, I can confirm that description, and also I've
confirmed that the sound is coming from the PC speaker.

The machine will sometimes post, and I can get into BIOS. If I let it
sit there in BIOS, the display eventually goes blank, and the monitor
LED blinks yellow, indicating that it's lost video signal. When it
does that, I start hearing the "static" sound from the PC speaker.

Sometimes it won't post at all, just a blank screen and blinking
monitor LED and the static sound.

We've unplugged everything except the video card and 1 RAM stick.
Still the same symptoms.

We've pulled the motherboard to check for anything underneath, but
found nothing.

I've found this post:

http://groups.google.com/groups?hl=...-8&[email protected]

and I thought might be the CPU seating, so we've also pulled the CPU
and heatsink, and reseated that and put the heatsink back on with
some new paste. Still the same problem.

I did notice that there's a small fan on the motherboard itself,
probably for cooling the chipset, and sometimes doesn't turn when we
power the machine on. If I push the fan blades, it'll start turning,
but seems a little slow.

When in the BIOS, I've set it to "Safe Defaults", but still the same
thing.

When I can get into the BIOS, the BIOS PC Health display, it shows:

Core 1.63V
3.3V 3.41V
5V 4.85V
12V 12.00V

I'm thinking that it's either a problem with the motherboard or with
the power supply (the slow fan?)?

Any thoughts/suggestions on this?

A friend is going to try to bring over a spare power supply for me to
try this weekend, but, also, if it turns out to be the motherboard,
can anyone recommend a reliable replacement motherboard?

I went to a local Microcenter, and all of the motherboards they had
only supported DDR or DDR400, whereas she has 3 sticks of 256MB PC133
SDRAM, so I'd like to reuse the RAM if we can.

Apologies for the long post, and thanks in advance!!

Jim

Sounds like there may be some bad caps on that older MB. Look for any
bulging and/or discoloration on the tops and/or bottoms of the
electrolytic capacitors on the MB.
Any caps that look anything like this?
http://www.careyholzman.com/caps/images/caps.jpg

 

[Ohaya]

Sounds like there may be some bad caps on that older MB. Look for any
bulging and/or discoloration on the tops and/or bottoms of the
electrolytic capacitors on the MB.
Any caps that look anything like this?
http://www.careyholzman.com/caps/images/caps.jpg

ICee,

I checked all the caps, and I found 3 caps that "may" be as you
indicate: EC23, EC24, and EC27.

I've posted a picture at:

http://members.cox.net/ohaya/motherboard.jpg

The 3 caps pointed to are different than your picture. They have a kind
of beige-colored residue on top, kind of reminds me of when battery acid
leaks from a car battery.

The EC27 seems (hard to tell) SLIGHTLY bulged.

The rest of the caps of the board are clean and no bulging.

So what do you think???

I assume that this is a multilayer board, so is it difficult to
desolder/replace these caps?

And again, if this board is dead, what would be a good replacement
(needs to support AMD Duron, and hopefully have 3 SDRAM slots)? The
KT7Es seem to be hard to find.

Jim

 

[Ohaya]

ICee,

I checked all the caps, and I found 3 caps that "may" be as you
indicate: EC23, EC24, and EC27.

I've posted a picture at:

http://members.cox.net/ohaya/motherboard.jpg

The 3 caps pointed to are different than your picture. They have a kind
of beige-colored residue on top, kind of reminds me of when battery acid
leaks from a car battery.

The EC27 seems (hard to tell) SLIGHTLY bulged.

The rest of the caps of the board are clean and no bulging.

So what do you think???

I assume that this is a multilayer board, so is it difficult to
desolder/replace these caps?

And again, if this board is dead, what would be a good replacement
(needs to support AMD Duron, and hopefully have 3 SDRAM slots)? The
KT7Es seem to be hard to find.

Jim

Hi,

Just in case, I checked the CMOS battery, and it's measuring 2.82V. Is
that nominal?

Jim

 

[ICee]

Ohaya wrote:

Hi,

Just in case, I checked the CMOS battery, and it's measuring 2.82V.
Is that nominal?

Jim

Yes, those three caps are definitely bad. They are all bulging on the
top and the beige colored residue is dried electrolyte. I see they are
near the AGP socket; are the ones near the CPU socket all ok? The CMOS
battery (if it's a CR2032) should be 3.3v. That is low, but would not
cause the symptoms you have. It's there to hold any changes you make to
the BIOS, such as date and time, and any settings other than default.

 

[ICee]

ICee wrote:

Yes, those three caps are definitely bad. They are all bulging on the
top and the beige colored residue is dried electrolyte. I see they
are near the AGP socket; are the ones near the CPU socket all ok?
The CMOS battery (if it's a CR2032) should be 3.3v. That is low, but
would not cause the symptoms you have. It's there to hold any
changes you make to the BIOS, such as date and time, and any settings
other than default.

Forgot to mention that the fact that the bad caps are next to the AGP
slot explains why you lose the display after a time.
I'm afraid I'm not familiar with any MB that would have slots for SDRAM,
since DDR has been out so long.

 

[Ohaya]

Ohaya wrote:


Yes, those three caps are definitely bad. They are all bulging on the
top and the beige colored residue is dried electrolyte. I see they are
near the AGP socket; are the ones near the CPU socket all ok? The CMOS
battery (if it's a CR2032) should be 3.3v. That is low, but would not
cause the symptoms you have. It's there to hold any changes you make to
the BIOS, such as date and time, and any settings other than default.

ICee,

Yes, all other caps, including the ones near the CPU socket, look
"normal" (no bulging, and no residue).

 

[ICee]

ICee,

Yes, all other caps, including the ones near the CPU socket, look
"normal" (no bulging, and no residue).

I was thinking that bad caps in the voltage regulator circuit near the
CPU would be more likely to cause the problem, till I reread your post
and saw that you lose the display after a time. The problem is
definitely the bad caps near the AGP slot.
Since a new MB with SDRAM is going to be difficult, if not impossible to
find, you may want to try getting that MB repaired. From what I've read
in these NG's, this place does a good job and the price is very
reasonable:
http://www.motherboardrepair.com/

 

[Ohaya]

I was thinking that bad caps in the voltage regulator circuit near the
CPU would be more likely to cause the problem, till I reread your post
and saw that you lose the display after a time. The problem is
definitely the bad caps near the AGP slot.
Since a new MB with SDRAM is going to be difficult, if not impossible to
find, you may want to try getting that MB repaired. From what I've read
in these NG's, this place does a good job and the price is very
reasonable:
http://www.motherboardrepair.com/

ICee (or anyone else),

I was wondering... With the bad caps, would it be ok to just cut the
caps off the board, and solder new/replacement caps to the leads that
are left on the board?

I have a supply of electrolytics (from "the olde days"), but I'd be a
bit worried about desoldering something on a multi-layered board, but I
think I could handle the above.

Comments?

Jim

 

[Ohaya]

ICee wrote:


Forgot to mention that the fact that the bad caps are next to the AGP
slot explains why you lose the display after a time.
I'm afraid I'm not familiar with any MB that would have slots for SDRAM,
since DDR has been out so long.

ICee,

Hmm. My testing was with a PCI video card, not with an AGP card. Also,
I get similar symptoms regardless of which PCI slot I install the video
card in...

 

[Apollo]

I was wondering... With the bad caps, would it be ok to just cut the
caps off the board, and solder new/replacement caps to the leads that
are left on the board?

I have a supply of electrolytics (from "the olde days"), but I'd be a
bit worried about desoldering something on a multi-layered board, but I
think I could handle the above.

Comments?

I'd give it a go, but consider that other caps will begin failing before
very long, this fault is very well documented.

Have a look here http://www.acme.com/build_a_pc/boardfinder/ to try and find
a board compatible with the sdram. May be time for an upgrade to ddr ram or
look on ebay for a used replacement board (bear in mind that a LOT of boards
around the age of yours will have failing caps).

You can pick up a new nforce2 mobo for around £25, XP2500 - £50, 512MB DDR -
£50. One thing to remember if you change your mobo - read up on removing
any traces of existing mobo drivers from your o/s before you shutdown for
the change, this should enable you to change without re-install of the o/s.

HTH

 

[Ohaya]

I'd give it a go, but consider that other caps will begin failing before
very long, this fault is very well documented.

Have a look here http://www.acme.com/build_a_pc/boardfinder/ to try and find
a board compatible with the sdram. May be time for an upgrade to ddr ram or
look on ebay for a used replacement board (bear in mind that a LOT of boards
around the age of yours will have failing caps).

You can pick up a new nforce2 mobo for around £25, XP2500 - £50, 512MB DDR -
£50. One thing to remember if you change your mobo - read up on removing
any traces of existing mobo drivers from your o/s before you shutdown for
the change, this should enable you to change without re-install of the o/s.

HTH

Ian,

Thanks, I think that I've found a reasonable substitute, a Soyo KT7VA.
I posted on the Soyo NG to see if anyone has any feedback on that
motherboard, e.g., regarding the caps.

Unfortunately, we'll have no chance to do anything with the drivers,
since the Abit is essentially dead/won't boot, so I'm planning to
re-install for her...

 

[Jens C. Hansen [Odense]]

The CMOS battery (if it's a CR2032) should be 3.3v.

No, it shouldn't.
A brand-new CR2032 measures 3.1-3.15 V, and should still be above 2.9 V
after a few years in a board.
2.82 V is on the edge of "the red zone", and I wouldn't expect the CMOS
to hold data reliably. It should be replaced.

 

[Frank Hagan]

"Thanks, I think that I've found a reasonable substitute, a Soyo KT7VA.
I posted on the Soyo NG to see if anyone has any feedback on that
motherboard, e.g., regarding the caps."

If you mean a Soyo K7VTA Pro I've built a few. Very solid board, but not
much for overclocking. It uses PC133 memory and you can't lock the PCI and
AGP busses.

FRH

 

[*Vanguard*]

"Ohaya" said in

Thanks, I think that I've found a reasonable substitute, a Soyo KT7VA.
I posted on the Soyo NG to see if anyone has any feedback on that
motherboard, e.g., regarding the caps.

Unfortunately, we'll have no chance to do anything with the drivers,
since the Abit is essentially dead/won't boot, so I'm planning to
re-install for her...

How old is the Abit motherboard? Under a year? If so, the warranty
will let you get it replaced. In fact, since Abit was one of the
manufacturers hit with the capacitors built with the stolen but
incomplete formula, they may replace it even if the warranty has
expired. Doesn't hurt to ask; however, I've yet to get a response for
any technical info question that I've submitted directly to Abit but
maybe they are more responsive regarding warranty replacement requests
(and they can less ignore you if you call them instead of use e-mail).

Abit was one manufacturer, maybe the only one, to admit they got stuck
using the defective capacitors. Also, the bulging leaky capacitors
provide a visual clue that they are bad. Could be others are also bad
that have opened up and dried out.

Some articles on the leaking capacitors:
http://www.spectrum.ieee.org/WEBONLY/resource/feb03/ncap.html
http://www.burtonsys.com/bad_BP6/story2.html
http://www.geek.com/news/geeknews/2003Feb/bch20030206018529.htm

 

[ICee]

No, it shouldn't.
A brand-new CR2032 measures 3.1-3.15 V, and should still be above 2.9
V after a few years in a board.
2.82 V is on the edge of "the red zone", and I wouldn't expect the
CMOS to hold data reliably. It should be replaced.

You're right, of course. It's a 3.0 volt battery, which will read
slightly higher when new, as you mentioned. So used to 3.3v being used
in the system, it just "came out" as such.

 

[Ohaya]

"Ohaya" said in

How old is the Abit motherboard? Under a year? If so, the warranty
will let you get it replaced. In fact, since Abit was one of the
manufacturers hit with the capacitors built with the stolen but
incomplete formula, they may replace it even if the warranty has
expired. Doesn't hurt to ask; however, I've yet to get a response for
any technical info question that I've submitted directly to Abit but
maybe they are more responsive regarding warranty replacement requests
(and they can less ignore you if you call them instead of use e-mail).

Abit was one manufacturer, maybe the only one, to admit they got stuck
using the defective capacitors. Also, the bulging leaky capacitors
provide a visual clue that they are bad. Could be others are also bad
that have opened up and dried out.

Some articles on the leaking capacitors:
http://www.spectrum.ieee.org/WEBONLY/resource/feb03/ncap.html
http://www.burtonsys.com/bad_BP6/story2.html
http://www.geek.com/news/geeknews/2003Feb/bch20030206018529.htm

Hi,

Well, I tried submitting something through their "e-rma" website, and it
came back and told me that the board was out of warranty and I had to
pay $25, so, despite my misgivings, I started working on the board .
So far, I've been able to remove the caps (EC23, 24, and 27). They're
all 1500 uF @ 6.2V.

But, I only have an old solder sucker, and am having problems getting
the solder out of the holes !!

Any suggestions?

Jim

 

[Ohaya]

You're right, of course. It's a 3.0 volt battery, which will read
slightly higher when new, as you mentioned. So used to 3.3v being used
in the system, it just "came out" as such.

Hi,

WHOO BOY, what a (bad) day ...

After all of this, I decided to bite the bullet, and we went out and got
a new MB, an ASUS A7V8X-X and a 512MB stick of DDR333 RAM.

Got that home, and guess what?

Yep, the new motherboard wouldn't POST. No beeps. CPU fan not turning.

Took the case, etc., motherboard to the store.

After a bit of tweaking, they got the motherboard booting on their test
bench.

I asked them to test the motherboard with my power supply.

Guess what?

Yep, no boot with our power supply and the new motherboard.

So, I bought a new power supply, and we brought the whole kit and
kaboodle back home.

I was curious, so I used the new power supply with the old Abit KT7E
(the one that originally had a problem), and guess what?

Yep, it booted fine! Mind you, this was with the 3 capacitors that were
bulging completely removed!!

Oh well, so it looks like I have 2 motherboards now , but to top it
off, I am now having problems with trying to install Windows XP with the
new Asus motherboard!!! I am getting a STOP error during the install,
saying the BIOS is "not fully ACPI compliant". I've already deleted the
original XP partition, so there's no going back to the original (now
working) Abit KT7E ...

I've posted my problem on the ASUS NG, so if any of you nice folks know
what might be going on with this, please let me know.

Thanks for your patience!

Jim

 

[*Vanguard*]

"Ohaya" said in

But, I only have an old solder sucker, and am having problems getting
the solder out of the holes !!

Any suggestions?

Try using solder wick (looks like a flat skinny strip of mesh copper).
Dab a bit of extra solder atop the tail from the capacitor or the
soldering pad and lay down the solder wick to absorb that solder and
hopefully pull out the other old solder. The more layers the PCB has
the harder it is to extract.

Since the capacitors are bad, you could try yanking them off the board
and just leave behind a remnant of their tails. Rather than pull away
from the board, just twist the capacitors like you're trying to screw
them on or off. Then the device can't absorb any heat. Be careful not
to overheat the board. So rather than trying to desolder the capacitor,
you destroy it by twisting it off, leaving behind the tails, and you can
then actually solder the pad to melt the old solder and get the tail
loose so you can use a pliers or cutter to grab the tail and pull it
free. Then solder the hole first to lay in new solder and use the
solder sucker to suck it all out.

Although tempting, I probably wouldn't use higher than a 15W soldering
iron, Make sure the tip is tinned and a apply a tiny dab of fresh
solder on the tip to let it cover the pad you're trying to melt of the
old solder. A little dab of extra solder that melts and lays atop the
soldering area transfers heat a lot better than you trying to get some
heat off the smaller surface of the end or side of the soldering iron
tip. Also be sure you are using a non-static solder sucker. Some
generate static. I'm assuming you've already taken other anti-static
precautions.

Note that just finding another capacitor of equal capacitance and
voltage is not sufficient. You need to also match the type of the
capacitor.

 

[Ohaya]

"Ohaya" said in

Try using solder wick (looks like a flat skinny strip of mesh copper).
Dab a bit of extra solder atop the tail from the capacitor or the
soldering pad and lay down the solder wick to absorb that solder and
hopefully pull out the other old solder. The more layers the PCB has
the harder it is to extract.

Since the capacitors are bad, you could try yanking them off the board
and just leave behind a remnant of their tails. Rather than pull away
from the board, just twist the capacitors like you're trying to screw
them on or off. Then the device can't absorb any heat. Be careful not
to overheat the board. So rather than trying to desolder the capacitor,
you destroy it by twisting it off, leaving behind the tails, and you can
then actually solder the pad to melt the old solder and get the tail
loose so you can use a pliers or cutter to grab the tail and pull it
free. Then solder the hole first to lay in new solder and use the
solder sucker to suck it all out.

Although tempting, I probably wouldn't use higher than a 15W soldering
iron, Make sure the tip is tinned and a apply a tiny dab of fresh
solder on the tip to let it cover the pad you're trying to melt of the
old solder. A little dab of extra solder that melts and lays atop the
soldering area transfers heat a lot better than you trying to get some
heat off the smaller surface of the end or side of the soldering iron
tip. Also be sure you are using a non-static solder sucker. Some
generate static. I'm assuming you've already taken other anti-static
precautions.

Note that just finding another capacitor of equal capacitance and
voltage is not sufficient. You need to also match the type of the
capacitor.

Vanguard,

Thanks. I saw your post too late though, as I'd already removed the
caps ...

I'll now go-a-searching for replacements, but FYI, I powered the board
on without the caps, and it booted fine!!

Are those caps (EC23,24, and 27) only noise suppressors?

Jim