Does a bulging capacitor automatically indicate "capacitor plague?"

Jester999999 said:

OK *edit* no one knows why this has happened...

Firstly I notice your overclocking. This is the reason the capacitor has swelled ... It is not a heat issue but instead an over voltage issue and the electrolytic capacitor is prone to swell if subjected to voltages beyond their specs. This is a common knowledge thing in electronics field.

In other words you pushed the voltage to far and the cap couldnt take it.

Easy way to see this happen and watch one pop is get a low voltage cap and wire it up to a higher voltage supply... it will pop like a fire cracker.

And it is NOT "capacitor plague" ... *edit*

Cleaned up your post, you have PM - I.M.O.G., Forum Admin

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Faulty capacitors on motherboards are a well documented issue. If you know your PC history, it often has little to do with whether components are ran within spec. For example, Dell has one of the most well known bad capacitor problems from their optiplex brand of desktops, which run locked down bioses and can't be overclocked or have their voltage tweaked through normal means. Here's one example of Dell's problems:
http://news.cnet.com/PCs-plagued-by-bad-capacitors/2100-1041_3-5942647.html

In overclocking, capacitors may be prone to failure more often due to heat and operating out of specs, however most people overclocking are using relatively high quality boards which typically use good quality capacitors. We run out of spec all the time, yet bulging and failing caps are relatively uncommon.

This post holds some of the folk lore about about bad caps, but denying the existence of widespread capacitor problems in systems ran at spec is not a valid stance - this is not a problem unique to overclocking, and the cause of the issue may or may not be overclocking. Lots of people overclock on boards with good quality caps and do not have capacitor failures:
http://www.badcaps.net/forum/showpost.php?p=1686&postcount=4

This thread lists known bad quality cap manufacturers present in PCs:
http://www.badcaps.net/forum/showthread.php?t=388

It got a lot of press, and you hear a lot less about problems these days, but that doesn't mean the problems are altogether gone - especially on boards built a few years back.

Authoritative explanation of issue:
http://badcaps.net/pages.php?vid=4

Identifying failed/failing caps:
http://badcaps.net/pages.php?vid=5

FAQ about bad caps:
http://badcaps.net/pages.php?vid=7

More voltage then the cap is rated for can (and will) indeed cause failure, which may be a bulging mode (too much voltage and they'll simply explode). However, with certain exceptions the caps are rated for 4 or more times the normal voltage for the platform and this is not an issue.
The narrowest margin i've run across is some gigabyte mobos, they use 2.5v caps on 775 stuff and you can set the vcore to 2v or so. That's a narrow margin.
My asus board uses 6.3v caps.

Anyway, if you have a bargain basement mobo then running 2vcore probably isn't a good idea. That said, 2vcore isn't a good idea in the first place.


So while Jester is correct that too much voltage can and will kill caps, i highly doubt that it is involved in the death of those. For giggles you can read the label on the cap and find it's voltage rating.

torin3 said:

Also, you can have caps go bad from 'dirty' power.

I work in a shop with about 100 lathes, mills and other machines that have any where from 1/4 HP to 40 HP motors on them. Our power is not anywhere near clean. We've had several computers develop bad caps on them from good manufacturers. We wound up putting almost all our computer on UPSs to cut down on the number of dead PSUs and blown motherboards.

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This is another major cause of caps going bad.

I have seen a TON of motherboards with swollen caps. Along with those boards were PSUs with caps inside them that were bulging or leaking from the same PC (mostly Delta, Bestec, Hi-Pro and some Antecs that were over 3 years old).

I've seen rubicon caps, chemicon, and some SSs burst or leak. These are brands that are known for their quality, but they can fail due to a poor source of power.

Another source of the problem are bad mosfets that overheat. We've had an issue with Asus where we would see signs of an overheating mosfet that would result in a dead motherboard with swollen/bursting caps. I've found this on P4P800 boards, P5RD2-VM, P5PE-VM, P5P800. Not all manufacturers are perfect (deliberately or by accident) and can sometimes bring out a product that's "defective by design".

Now, just recently I swapped out the caps for a mATX board. The first set of caps I replaced were these 6.3v 1800uF caps on the CPU VRM side. A month later the motherboard started to BSOD and turns out a cap on the RAM VRM side, which is also a 6.3v 1800uF cap but was original, was starting to burst. So, I ended up replacing the remainder of the original caps of that type on that board.

madhatter256 said:

In my experience, if it's a brown cap, then it's from one of the low-quality brands motherboard makers put in to squeeze out profits.

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Not always true. Nippon Chemicon are good caps, but the KZGs seem to have low limits of temps.

The caps I'm more worried about are silver caps that look like polymers with a blue stripe and says "FZ".

(Because the "FZ" caps are from the same company that brought us GSC caps)

Common on eVGA video cards.

Jmtyra said:

Only if it's a Dell.

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Or a MSI P4 board. I've seen them all ready to pop.

EarthDog said:

So a capacitor goes bad and instatly goes back to caps made in 99-07? I guess that board was made around that time...

Thanks for the info!

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The worst was 2000 to 2004... Mostly the socket 462 era...

It all comes down to temp, AC current through the cap, and how close to the rated voltage the cap has on it.
While overclocking will not run a cap over it's rated voltage, it can exceed the rated AC current for that cap and make it blow.
If a cap for example is rated for 12V and it has 13V on it, it will blow but slowly, but put 100V on it and it will go bang.