Taiwanese Capacitors Leaking, Exploding

ackthpt writes "A few astute slashdot readers were on to something back when this article was published. After a tip (at e-insight.net) on failing caps over at amdmb I did a little looking around and found this article by Dennis Zogbi on TTI Inc.'s site, which goes into more detail. In a nutshell, many motherboards are now failing due to electolytic capacitors made with an inferior water-based electolyte. Within days or a few months these capacitors build up hydrogen gas and blow the rubber bung out the end of the capacitor, leaking electolyte and causing havoc. The problem may be widespread, as many consumer electronics made with these capacitors may also fail prematurely. Gary Headlee specializes in Abit motherboards, but as his FAQ states, he will work on other makes and the FAQ has more info on capacitor problems."

Comments

Recalls?

[Anonymous Coward]

Good god...how many of these things could be lurking about in automotive airbags, ABS systems, or in any sort of medical device?

Re:Recalls?

[sigwinch]

I think that's overly harsh on electrolytics. Like everything else, what you get depends on what you buy. You can buy from respected companies that have been making good caps for 20 years, or you can buy from whatever random Chinese company was cheapest this week. You can settle for any specs you can get, or you can insist on caps that are rated for 5000 hours of operation at 105 degrees Celcius (hotter than boiling water!).

There are also system design issues. You can push the caps to the very limit of their rated ripple current, or you can use more caps and share the current around.

Good god...how many of these things could be lurking about in automotive airbags, ABS systems, or in any sort of medical device?

For the most part, none.

Medical stuff routinely uses electrolytics. It doesn't have to be perfect, it just has to fail a lot less often than doctors and nurses.

Electrolytic capacitors have a fixed lifetime and are by nature unreliable.

They do not. The lifetime depends on the grade selected by the engineer, and how hard the design pushes the cap. A good cap used properly can last for many years of continuous service. That's good enough for many applications, even in safety-critical systems.

Where reliability is critical, Tantalum capacitors are used, but they're physically larger and more expensive.

You can't be serious! Tantalums are notoriusly flaky. Not only that, the usual failure mode is that the cap vanishes in a spectacular flash of purple fire. Every capacitor failure I've ever seen in computing equipment has been a tantalum. An engineer who used to work at Motorola told me that tantalums were banned from pager designs. At the time, Motorola would rather pay the premium for ceramic caps than risk tantalums.

Any -critical- system manufacturer(automotive safety systems, medical equipment, etc) that uses electrolytic capacitors should be shot.

It depends entirely on the service life that is needed, and the degree of redundancy you can afford. Satellites and airbags have to remain in service for decades without repair, so electrolytics are probably unacceptable. Medical equipment generally doesn't need such high reliability, and frequently uses electrolytics. (Seriously. Med equipment is regularly replaced, there's no point in making it more than a couple of orders of magnitude more reliable than physicians, and the critical stuff has spares sitting on shelves.) Telecom equipment can afford redundancy in almost everything, and so it's full of electrolytics.

Re:Recalls?

[pz]

You can't be serious! Tantalums are notoriusly flaky. Not only that, the usual failure mode is that the cap vanishes in a spectacular flash of purple fire. Every capacitor failure I've ever seen in computing equipment has been a tantalum. An engineer who used to work at Motorola told me that tantalums were banned from pager designs. At the time, Motorola would rather pay the premium for ceramic caps than risk tantalums.


He was serious, and so am I when I say that I routinely design with tantalums when I want high reliability, electrolytics when it doesn't matter as much. The fellow you mention from Motorola (and his associates) don't understand the problems with tantalums: they are extremely reliable, and have far superior specifications than equivalent electrolytics, if you simply derate the maximum voltage by a factor of 2. Eg, if your design calls for the capacitor seeing a maximum differential of 15V, specify a 30V capacitor.

My father, also an electrical engineer, and I have separately been doing this for decades (him, something like 5, me, something like 2) and not seen a single tantalum failure. My father used to see a lot of tantalum failures until he took the time to understand the failure conditions and derated the specs. But, this applies when the options are electrolytic or tantalum.

When the options are ceramic or tantalum, as you suggest with the fellow from Motorola, there's a huge difference. Ceramics are not available in value ranges that electrolytics can be manufactured in (in part because it's difficult to make a realllllllly thin sheet of ceramic, plate it on one side, and roll it up). Ceramics, for the same value range as tantalums, have superior specifications but larger physical size, as long as you stay away from the lower end of the quality spectrum. Comparing, however, the selection of tantalums over electrolytics against ceramics over tantalums is, well, like two different kinds of fruit.

In sum, given my druthers, in larger values, it's tantalum, unless the value range necessary or cost contstraints precludes them, in which case the choice is electrolytics. In smaller values/higher frequencies, it's ceramic.

My MSI board failed.

[dsb3]

My MSI board failed a couple of months ago, and we didn't have a dog to blame the smell on.

I noticed many of the caps around the memory banks appeared blown - there was a lot of brown residue around the top. The smell occured a week or so (perhaps?) before final failure.

For my money, even though the original board cost around $120, I just bought a $50 replacement from ECS. It took most of the original memory (2 DIMM slots only, compared to the 3 slots in the original), and otherwise did what was needed without spending repair money on what's now an old-tech product.

The machine has an Athlon 900 T-bird, now has a 1/2G of ram (did have 3/4) and doesn't really do a great deal other than email, web, games, photoshop. Sure, the extra 1/4G of ram would have been nice to keep but for the money of even thinking about the repair I'd be better off just recycling and buying new with a DDR333 system.

Once again, technology is cheaper to replace/upgrade than it is to repair.

shopping list?

[visualight]

I'm in the middle of shopping for a new board. Now I'm afraid to make a decision until I can find a list of boards that are "safe". If anyone finds such a list please post it!

Cheap capacitors

[HotNeedleOfInquiry]

Nothing new about the annoucement. Cheap electrolytic capacitors have been around and been a problem for years. There are other failure modes. i've fixed several old Mac's where the cap has pissed it's electrolyte all over the motherboard. Usually removing the cap, scrubbing the board and installing a new cap fixes the problem. Even worse is when the electrolyte is lost gradually. The product that it's in gets flakey over time and the problem is very hard to find. These problems are all made worse by exposing your gear to high temperatures. Never leave your electronics in the passenger compartment of your car in the summer.

Not the only problem

[Bobulusman]

It seems that motherboards in general are being made more poorly lately. Last April I bought a Soyo Dragon Plus motherboard. It has been give me and others problems. Apparently, they screwed something up because the board is not technically PCI compliant on the top two pci slots. So basically, if you use the AGP slot and either of those slots with anything more taxing than a modem, you will be riddled with reboots and the like.

Not to mention that there is something else screwed up with the board because the MadOnion benchmark always identifies it as having twice as much ram as it does (I have 512 mb on two 256 mb's. It thinks I have two 512 mb's) and it can not seem to complete the PCMark test without rebooting during the ram tests. This has happened to other Soyo Dragon Plus users, so it's not like it's just the software.

And don't even get me started on how they ripped me off by not bothering to tell me that they would not give me the accessories needed to make various functions work. Had to by them seperately....

Same case with the motherboard I bought before that.

Anyway, my point is that it just seems that MB manufacturers are cutting a lot of corners, so it doesn't surprise me that they are using cheap capacitors.

Isn't Anyone Doing Qualification Testing?

[Anonymous Coward]

Yes these are obviously bad components but I am curious. Do consumer electronic manufacturers do any type of development validation or component qualification testing?

In the automotive world, this would have been caught way before production started, unless of course, the component supplier changed the electrolyte type without notifying its customers after start of production.

The amount of testing that occurs on automotive electronics is sometimes thought of as gross overkill. When I hear stories like this, it reminds me of why.

Tanatlum shortage

[huie]

Do a Google search on "tanatlum shortage" and you'll see that there was a flury of articles about a year and a half ago. This prompted development of other electrolytic capacitors, one of which is the aluminum electrolyte that seems to be having problems.

I assume that it's only taken this long to find the problem due to the development time and time to qualify (ha!) and integrate these new caps onto boards. Needless to say, I guess they needed to develop the caps better, but they may have rushed to market since there was little else available (at a decent price).

Sun mainboards too.

[jmajb]

We have 9 Sun Ultra 10 stations. Because there were some problems with the PCI cards (add on PC card), we opened one. We choose the Sun which seemed to have some loose parts inside. After opening it appeared to be the cap of a capacitor, which lay loose inside and was completely swollen. Almost all of the other capacitors were leaking. This was not incidental, then the other Suns had the same problem. We contacted Sun, who said that the problem did not exist... Do the Ultra's work, theya asked. To our amazement, we had to reply: yes. So what's your problem, was their reaction. Jac

MSI K4 Ultra info

[ackthpt]

An associate just picked up an MSI K4 Ultra during lunch. It has Rubycon (jp) 3300uf and some G-Luxon (tw) caps in the power converter and a few Nichicon (jp) scattered around the board.

G-Luxon has this insightful bit on their news page:

recently, a rumor says that some of the customers (I company in USA, F company/ M compnay/ S company in Japan) are worrying about the quality of Aluminum Electrolytic Capacitor from Taiwan Manufacturers. It has resulted in a storm during Taiwanese suppliers. We are badly worrying this ill news is getting to harm LUXON'S reputation. According to the information, it was caused by some of manufacturers- L company and Y company, have failures in their products and it was raised by that L company and Y compnay used the electrolyte P-50, P-51 which are from a company named "LENYAN". For this reason, many customers misunderstand all of Taiwan Aluminum Electrolytic Capacitor Manufacturers are using the electrolyte including P-50 and P- 51. LUXON definitely understands that the electrolyte is one of the most important materials for Aluminum Electrolytic Capacitor. In order to ensure our reliability and innovative technology, LUXON always develops the electrolyte by ourselves. We hereby declare that: LUXON ELECTRONICS CORPORATION DO NOT HAS ANY BUSINESS WITH "LENYAN" AND DO NOT EVER USE THE ELECTROLYTE CONTAINING P-50 AND P-51. We are sorry to hear that this ill rumor released by unknown defamer has caused unnecessary anxiety to our customers. We have to make the truth clear. We guarantee that our products do not use the electrolyte including P-50 and P-51. Sincerely wish having your always support and encouragement to LUXON as usual.