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Technology Hardware

PCs Plagued by Bad Capacitors 335

Posted by CowboyNeal from the enemy-within dept.
Hawaiian Rules writes "CNET has a story detailing a new threat to Dell PCs, Apple iMacs and other computers with Intel boards. This has been documented on BadCaps.net for some time, but the article also discusses what to do if you suspect you've got a case of the bad caps."
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PCs Plagued by Bad Capacitors More

PCs Plagued by Bad Capacitors

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  • More than just Intel boards (Score:3, Interesting)

    by starbuck8968 ( 224854 ) on Friday November 11, 2005 @12:37AM (#14005015)
    I've had a couple AMD boards go bad because of leaky capacitors.
    • Epox, Asus, Abit have all had bad caps on a few boards for me. Not exactly wide spread, I'll have 3 or 4 of the same board and only one will fail. But its something I've noticed with about every manufacture so far. Manufactures so far have been excellent on RMA'ing the product quickly.

      On our systems with UPS's this seems to happen less often, my guess is the cleaner power puts less stress on the board.
    • I've had a couple AMD boards go bad because of leaky capacitors.

      That's nothing. I work at a university where we purchased hundreds of the Dell GX270 a couple years ago. In the last year we've had almost all of the fail on us (we are expecting all to fail in time). The worst part is that we've had to wait up to 4 weeks to get warranty service when we paid for NBD service. The hold up we were told was due to backorder.

      The warranty service tech tells us the problem is with the faulty capacitors. Gotta
      • We have had numerous failures of GX270's as well.
        Our service has been great, I just didn't like that until now Dell would not admit there was a problem! When you see the same problem on a second board, you start to think there might be an issue. Then the tech tells you they have been having problems on these boards....but when you phone dell, and say you have had another board go down with leaky caps, they pretend like they have no idea what you are talking about :P

        • Re:More than just Intel boards (Score:5, Interesting)

          by Anonymous Coward on Friday November 11, 2005 @03:32AM (#14005779)
          I work for HP's customer support. If you tell the customers about internally known issues, you can get fired for it. The reason? The customers may go to the press and say that HP knows about a problem but isn't doing anything about it (like a recall of all units for instance). HP looks bad if you say you took "5 calls just like this one" today. HP looks good if you instantly order a repair on a seemingly unknown problem. The exception is for class issues, i.e. issues that are known to the public due to media exposure. It's part of the agent training to pretend we're oblivious to all problems, yet magically know how to solve them anyway.
      • I work at a university where we purchased hundreds of the Dell GX270 a couple years ago.

        Well look at that. We're not alone in the world after all.

        My workplace also purchased a whole bunch of GX270's a while back, and we too are having them fail on us at an impressive rate. It's interesting because I always thought that Foxconn motherboards (what Dell uses) were pretty reliable and well made.

        The crappy part is that we have all these systems under same-day warranty, but because they are backlogged with so m
        • Had the same exact problem here, but once I met with their account rep we got a bit higher model as replacements. If you have a bunch of computers go bad, and you've paid for same-day service, they have to rectify your situation. If they don't, threaten to disolve the contract and they'll listen to your terms.
    • More than just PC boards. My TEAC 80cm telly went bung about 18 months ago, and my parents' identical model went 6 months later. Bad caps, $180 repair bill.

      My in-laws' Netvista fell over last week, lots of magic blue smoke and 3 stuffed capacitors. The twin of that machine blew up 4 months earlier.

      The air flow & knock sensors in my car went - $1450 repair bill. Is there going to be a class action? If so, that was the capacitors.

      Gotta go... my washing machine is making funny noises.

  • Problem's been around for awhile. (Score:5, Informative)

    by Gilmoure ( 18428 ) on Friday November 11, 2005 @12:37AM (#14005016) Journal
    Bad Caps have been a problem since 2002 at least. For awhile, I was making some bucks repairing Apple Airports, with all their bad caps.
    • The problem with the Airport base station capacitor failures is described on this web page:

      http://www.vonwentzel.net/ABS/Repair/ [vonwentzel.net]

      There are also instructions buying and replacing the failed parts, with good images. I followed these instructions a couple years ago very successfully.
    • *chuckles evilly* I got to see a room full of people hit the floor when a Cap blew up in a machine located at the front of a lab. They thought someone was shooting at them.

      Our supplier (which is staffed by a couple of people that I am now rather good friends with) got a laugh out of the story too. It was the first bad cap we'd had out of a couple hundred machines we ordered from them so it was just one of those things.

      Still not as bad as the machine that literally caught fire one February morning a year

    • Re:Problem's been around for awhile. (Score:5, Funny)

      by penguinoid ( 724646 ) on Friday November 11, 2005 @02:42AM (#14005583) Homepage Journal
      Bad Caps have been a problem since 2002 at least.

      I THOUGHT COMPUTERS WITH BAD CAPS WAS A PROBLEM SINCE THEY INVENTED CHAT. That has to have been well before 2002.
    • Ever hear of a DSM? It's "Diamond Star Motors", a joint venture between Mitsubishi and Chrysler. Their first generation (1989-1993) Mitsubishi Eclipse, Eagle Talon, and Plymouth Laser is notorious for leaky caps which renders the ECU useless, thus rendering your car useless. New ECUs are around $1000 I believe, so many first generation DSM owners like myself replaced the old ones by hand. Unfortunately this problem didn't show up until after the warranty expired, but it was still a very common problem.

      Fa

    • I used to work at a South Florida radio repair facility in the late 80s, early 90s. Ford radios from that time were plagued with leaky electrolytic capacitors made by Nichicon. Ford had to use the very short (around 5mm high) caps to fit under the tape deck (and some model radios used 57 of the short capacitors). Delco (now Delphi) had to use the same height ones to fit under the heat sink. Bose used them (regular height) in their amplifiers. The electrolyte in the cans would leak, and sometimes boil out. W

  • If you don't wanna get ripped off. (Score:3, Insightful)

    by neologee ( 532218 ) on Friday November 11, 2005 @12:37AM (#14005017) Homepage
    Never buy brand new high-tech toys before they've actually passed major consumer testing.

    It's the same for everything technological! Only through trial and error, consumer brute force sort of do they get the best product after 1-2 years for most products such as Dell's, i'd cite motor companies too but bah.

    • Re:If you don't wanna get ripped off. (Score:4, Insightful)

      by lbrandy ( 923907 ) on Friday November 11, 2005 @12:48AM (#14005078)
      Never buy brand new high-tech toys before they've actually passed major consumer testing.

      It's the same for everything technological! Only through trial and error, consumer brute force sort of do they get the best product after 1-2 years for most products such as Dell's, i'd cite motor companies too but bah.       Well, considering electrolytic caps [cwru.edu] were invented in the 30s, I'd think we've given them enough spin-up to get that newfangled technology under control. The problem here is just poor quality control and cost-cutting. Luckily in the free-market, this type of things tend be a short-lived trend... it just requires the spotlight.
      • The BIG problem is that vendors often change the way components are made without telling you

        Back in the early 80s, I worked for a defense contractor. One of the units we made used a FET (Field effect transistor) - a nice standard 2n number if I remember right. Well, one day, about every 3 or 4th unit we made failed ONE test, and all symptoms pointed at the FET - you'd change it, and sometimes it would go away - luckily, we saved the "BAD" FETs - it seems that ONE of the manufacturers had "Improved" their

    • Re:If you don't wanna get ripped off. (Score:5, Interesting)

      by ebrandsberg ( 75344 ) on Friday November 11, 2005 @12:51AM (#14005096)
      Actually, I would go against this--something totally new and expensive will probably make use of better quality components. It is after they have been in the market for a while that they go cheap as they sell in mass and drive price down. Ever notice how old CD's lived forever, but new CD's scratch if you breath on them? I had one of the original 42 inch plasma screens, and it was built like a brick, I don't think I trust the new ones, they are lighter, thinner, and IMHO, built to be cheap, not last forever.
      • With respect to capacitors, I don't think it makes any difference, new or old, one of the cap manufacturers blamed for problems this time had a very solid, long standing track record.
        • How true, but when you cobble a bunch of expensive new stuff together with no history of how long it will work, and you are going to charge an arm and a leg for it already, will you risk blowing the whole thing on a cheap capacitor? The point is that at the introduction of a totally new product from a major player, in particular when they don't know how well they are going to sell, they don't want to ruin the market with a bad product launch. They use the cheap stuff (like the ipod nano screen issue) afte

      • Re:If you don't wanna get ripped off. (Score:5, Interesting)

        by earnest murderer ( 888716 ) on Friday November 11, 2005 @01:32AM (#14005306)
        The capacitor issue is more widespread. The problem isn't that they are low quality, it's that a particular MFR was using a stolen and bad formula for fluid for a long while before they began to fail. These capacitors are in everything, cheap stuff, spendy stuff and everything in between. Badcaps.net explains in detail...

        On the theme of new and expensive, I'm a little suprised that motherboard MFR's that make high end boards for enthusiasts (you know the ones, with ugly flourecent plastic bits and silver paint and whatnot) haven't used any SMC caps for these boards. You only see them on prototypes. I'd think if there was a market for a motherboard with yellow PCI slots and a purple PCB that this would be a much more attractive option.

        On the other hand, I suppose it costs nothing to make lime green and orange connectors, but actually making something nice would cost a few dollars.

        • Re:If you don't wanna get ripped off. (Score:3, Informative)

          by Anonymous Coward

          On the theme of new and expensive, I'm a little suprised that motherboard MFR's that make high end boards for enthusiasts (you know the ones, with ugly flourecent plastic bits and silver paint and whatnot) haven't used any SMC caps for these boards.

          I'm surprised that you're surprised. SM capacitors are usually much smaller values used for decoupling the supply pins of individual chips (ceramics typically 0.1-0.47uF), or low values for minor ripple filtering (tantalums up to 10-22uF). The electrolytics (

        • I'd think if there was a market for a motherboard with yellow PCI slots and a purple PCB that this would be a much more attractive option.

          It gets even more ridiculous than that. Remember that AOpen motherboard with the vacume tube amplified built-in sound card? Yeah, that's what I need! Bugger the high quality core components! I need extra harmonics! Warm sound!

          This all comes down to marketting. Most people don't know what they need or should wan't, so what they want is dictated to them by the companies who

    • Nothing to do with brand new high-tech (Score:5, Informative)

      by HotNeedleOfInquiry ( 598897 ) on Friday November 11, 2005 @01:27AM (#14005277)
      The caps were made by Nichicon. Nichicon has been in business for 50 years and has had, up to now, the reputation of building *the best* low esr high quality electrolytic caps on the market. I've specified Nichicon caps only in designs because they work better than anything else.

      That's why this is such a surprise.

      I know it's bad form to bitch about moderation, but I can't see any way that the parent is insightful. Nichicon has produced good caps for years. Manufacturers pay a premium for Nichicon caps. Something or someone fucked up a Nichicon. Has nothing to do with trial and error.
    • Very little can be done about bad caps. bad capacitors have been a problem with electronics sense .. well.. they were invented.

      A cap is basically a chemical rechargeable battery made for quick charging and discharging. The best you can hope for is the use of high quality chemicals. You have to understand however the people who make them make millions of them and its very difficult to maintain a low impurity count in the chemicals while still making a profit.

      There is a reason why most electronics have a 90 w

  • Not the first time (Score:5, Informative)

    by Racher ( 34432 ) on Friday November 11, 2005 @12:38AM (#14005021)
    I had this happen to an old Asus board I had a couple year ago. It was covered on /. before.

    Slashdot - Taiwanese Capacitors Leaking, Exploding [slashdot.org]

    Watch out for all the 'Geeks popping a cap in your mother' jokes.

    -Eric

  • What to do if you have a Bad Cap: (Score:3, Funny)

    by racecarj ( 703239 ) on Friday November 11, 2005 @12:40AM (#14005033)
    Call Capman

  • Nothin new here. Just like Car Makers. (Score:5, Insightful)

    by Vorondil28 ( 864578 ) on Friday November 11, 2005 @12:44AM (#14005051) Journal
    If a car maker can get away with a cheaper, flimsier [insert part here], save a few cents on each car, and sell millions of cars, they can make a mo'load more profit than if they'd gone with the slightly better quality part on every car. Same thing here only with mobos and capacitors -- nothing new.
    • Same thing here only with mobos and capacitors -- nothing new.

      I don't know about that. I've been into this hobby for a long time and it seems as though quality in all forms of electronics has taken a major dive since the late 90s. I certainly don't remember any of my XT and AT boards ever having bad caps, but I've had my fair share with ATX.
    • No joke there -

      Ford put plastic water pump impellers in Duratech engines found in Contours, Escapes, and others... a few cents off the cost, and they're MTBF is 40k miles - perfect. Just long enough to get out of warranty, but not long enough to not make money on the repair.

      Now look, Dell's paying for it out the arse this quarter because they had to go fix all their Optiplex. Good - they should have paid attention and bought the three cent caps, not the two cent deals.

    • Re:Nothin new here. Just like Car Makers. (Score:5, Informative)

      by HotNeedleOfInquiry ( 598897 ) on Friday November 11, 2005 @01:31AM (#14005302)
      But that's not what happened. The capacitor company in question, Nichicon is, or rather was, the best in the business. Manufacturers pay a premium for Nichicon caps because they were the best available. The motherboards in question were made by Intel and Intel uses quality parts.

      The problem is that Nichicon screwed up somehow, not that Intel got burned for buying the cheapest parts.

  • Happened to me.. (Score:3, Informative)

    by toupsie ( 88295 ) on Friday November 11, 2005 @12:44AM (#14005053) Homepage
    My Rev. A iMac G5 had this issue. After dealing with the AppleCare India division and proving that my Crucial RAM did not cause the failure, I was able to take it to a local Apple Store and they fixed my iMac in 4 days and returned it. Haven't had an issue since. My father's iMac Rev. A has failed twice. Apple replaced it with a new iSight iMac.

    You can read the whole history of dying iMacs on Macintouch [macintouch.com].

    • When the summer 2000 iMacs were launched, I was working for an Apple dealer. We had to replace analog/power boards in so fucking many of those things that to this day I HATE summer 2000 iMacs.

    • you broke the first rule of computer warranties. if your stuff breaks, remove any 3rd party hardware that you possibly can out of it, lest the manufacturer tries to blame the 3rd party for the 'failure'
  • My Dad bought a microcontroller-based water pump for construction work that had bad caps. You would think that companies would try to shave a nickel off a less vital part.

  • So? (Score:2)

    by theJML ( 911853 )
    I had this happen on an Asus motherboard I got in 2001, noticed it when I was swapping out RAM in 2003. Board still works to this day, but you can see a line going from one of the regulator caps down to the PCI slots. I wrote down what kind of cap it was in case I was bored and wanted to replace it.. but honestly, after almost 5 years with this T-Bird board, it's not a big worry of mine. Still running, still over clocked, still a heck of a Linux system.

  • Modern Times (Score:5, Funny)

    by Doc Ruby ( 173196 ) on Friday November 11, 2005 @12:51AM (#14005097) Homepage Journal
    The Internet really has become quite a zoo. Once the chairman of IBM thought "there is a world market for maybe five computers" [chrononhotonthologos.com]. Now there's a server farm just for bitching about bad capacitors. We really live in an age of miracles.

    • Re:Modern Times (Score:3, Interesting)

      by shanen ( 462549 )
      That's almost surely an urban legend. On the other hand, I heard that IBM had some similar problems with bad capacitors a few years ago. Affected a pretty large number of NetVista models, I think, though the absolute numbers of bad motherboards wasn't so bad... I don't know any of the details, but I have a fuzzy recollection that most of the bad capacitors were traced to a particular source in Taiwan.

  • After I knew what they looked like (Score:4, Insightful)

    by saskboy ( 600063 ) on Friday November 11, 2005 @12:52AM (#14005104) Homepage Journal
    It was easy to spot obviously bad capacitors once I knew what they looked like. The ones I notice look like little cylinders on metal legs, with a rounded instead of flat metal top.

    My least favourite kind of capacitor though, is one that works properly, but has been put in the worst place possible so that putting the heat sink on that is supposed to match the CPU, is impossible. And you can't exactly bend those suckers over out of the way, so you have to buy another heat sink that conforms to the annoying motherboard layout.
    • ... with a rounded instead of a flat metal top

      These are easily tested using the patented Bugs Bunny artillery shell quality control inspection procedure: Tap sharply with a hammer and if you are still alive, write "dud"..er.."good" on the side with a sharpie.

      Seriously, this sounds like a double foulup by Nichicon. Overfill with electrolyte so there is insufficient airspace for thermal expansion, then screw up the emergency vent hole at the bottom so the thing has no choice but to burst. I've blown pl

  • it's not that hard to fix (Score:4, Informative)

    by Squigley ( 213068 ) on Friday November 11, 2005 @12:53AM (#14005112) Homepage
    Ok, I realise most people (in general, not the /. population) probably wouldn't know which end of a soldering iron to hold, but it's not that hard to fix the issue..

    Read the values of the leaky caps, get replacements, or near enough in value replacements. This will probably cost about $5.

    Desolder the old caps, use a stainless steel pin to clean the solder out of the hole (since solder won't take easily to stainless), pop the new cap in (with the correct polarity), and solder it.

    I had an asus board go like this a couple of years ago, it took me about 1/2 hour to fix the issue, but most of that was getting the board out of the case, and reinstalling it.

    I called up asus, and had a runaround, before I identified the caps as the issue, and decided to fix it myself.

    I doubt it's going to cost $300 million dollars to fix this. I'm typing this on a GX270, and it's had the motherboard replaced in it already, but I don't know if caps were the reason for that.

    It's my work machine, first the hard drive died, so I called Dell and got it replaced, then the mobo died, and I just called Dell and got it fixed, I didn't investigate the issue myself, like I would have done if I owned the equipment, or if it was out of warranty.

    Anyway, while it might cost them a bit in labour, the hardware's not going to be all that much, replace the first few boards with working ones, then refurb the retrieved boards, and use those to replace the dodgy board, rinse, repeat.

    • Re:it's not that hard to fix (Score:5, Informative)

      by labnet ( 457441 ) on Friday November 11, 2005 @01:21AM (#14005246)
      This is where a little bit of knowledge can be a bad thing.

      Sure its easy enough to go to the local electronics store, and buy an equivilent cap (ie match the Voltage and Capacitance written on the cap), but there are a couple of other very important (depending on the application) normally not marked parameters.
      Ripple Rating, Temperature, and ESR
      ESR = Effective Series Resistance and can cause stability problems if it is too high.
      If the Ripple Current Rating is too low, you could end up with more exploding / dying caps due to over heating.
      If you do decide to DIY, I suggest you buy 105oC, low ESR caps. (And don't forget they are polarised. Putting them in backwards will make them explode)
      • Well, the previous cap blew up - pretty much anything you replace it with will be better and will last longer...

        I've had this issue on IBM and VIA mother boards. It seems to affect all makes of machines.
      • (And don't forget they are polarised. Putting them in backwards will make them explode)

        The best looking cap explosion I ever saw, was a tantalum which I accidentally soldered in the wrong way, while building a digital frequency meter.

        Once it came time to test... a small bit of the top popped off and a silver molten stream of what looked like beads of mercury came gushing out and off that stream came lots of smoke. It looked so cool I half did not want to switch it off. ; )

      • This is where a little bit of knowledge can be a bad thing. ... If you do decide to DIY, I suggest you buy [fancy caps]

        A lot of knowledge never makes up for bad judgement. It's broke, what you do won't make things worse. This is a case of little to lose and something to gain.

        The board is dead or flaky because it has cheap caps. Do you think putting new cheap caps will be worse? The worst you can do is screw up the traces with a cheap soldering iron. Then your dead board remains dead and you move on.

    • I'm no electronics guru, but I've recapped many (hundreds of) bloaty unstable boards in the last few years - I hate seeing them thrown out for no cause. I now collect them from computer stores.

      It's amazing how little work is required to do this once your on a roll, and does wonders for ones soldering skills.

      While I've found nothing is better than using brand new caps, I've found boards that die from other causes (eg, idiot techs with slipping screwdrivers) are a good source of the right size salvageable cap
  • I got hit with 4 bad Abit boards in 2001 back when it was first reported several years ago. I had assumed since then Taiwanese manufacturers would have stopped using the knock off capacitors or would have stolen/bought the correct formula if only to stop threat of lawsuits.

    I guess the lawsuits never came. Maybe it would be one time sleazy lawyers could do some good? It is pretty sad that electronics from ten years ago are better quality than todays and they know exactly why and yet it isn't fixed...

  • CAPS BAD? (Score:5, Funny)

    by Anonymous Coward on Friday November 11, 2005 @12:56AM (#14005129)
    ME NO UNDERSTAND!

  • Not new at all - quite a few Rev. A iMac G5s had this problem. I bought this 17" in November, and the bad caps finally failed in March. Apple sent me a new midplane and I swapped it out myself, but from what I hear they're now requiring people to take their machines to an authorized Apple service provider to get the work done.

    I took pictures of the midplane/motherboard replacement process [flickr.com], clearly showing the bad/bulging caps on the original system board.

  • I was working at a local computer shop and we got a bad batch of Amptron mobos that had substandard capacitors on them. Ususally, when they failed, it was within one minute of powering up. So we'd put them on the bench, cover the caps with the manual and power them up. If the caps didn't blow after one minute we'd put them in the systems.

    LK

  • bad caps (Score:5, Funny)

    by iggy_mon ( 737886 ) on Friday November 11, 2005 @01:06AM (#14005177) Homepage
    if you suspect you've got a case of the bad caps

    yeah, this one time in college, there was this girl... it was my first time, not hers though... i didn't know...

    oh! caps! never mind...

  • This has been a real hassle for me. (Score:3, Interesting)

    by mhore ( 582354 ) on Friday November 11, 2005 @01:17AM (#14005223)
    I inherited a bunch of 3 GHz P4 Optiplex machines back in '03 after they were decommissioned from a student computer lab. The university buys cheaper machines as they only keep them around in the labs for a year or so normally.

    Well, I roped them together into a really nice Beowulf cluster for running my simulations and for the past 2 years I've had nodes die left and right. I'm sure the machines are out of warranty now, but I really hope Dell fixes these machines. I seem to remember Gateway doing this back in 2002. Now that the official word is out, maybe the computer department will take my word for it. What does a silly physicist know about computers and motherboards anyway?

    Mike.
    • Decommissioned 3 GHz P4's!

      Christ, I work for a major telecom company where they make software developers use 900 MHz PIII laptops.

      • Decommissioned 3 GHz P4's! Christ, I work for a major telecom company where they make software developers use 900 MHz PIII laptops.

        Yeah, crazy isn't it? I couldn't believe it when I heard it. They update the hardware at the beginning of each fall semester in the student labs. Nice new flat screens, etc. Whatever the fastest-latest-greatest is that Dell offers. Then they distribute the "old" machines to faculty members, GAs, etc. I was lucky to get an entire lab's worth. I just wonder what kind of money th

  • Stamped with an "X" on top ? (Score:5, Informative)

    by aspeer ( 131086 ) on Friday November 11, 2005 @01:21AM (#14005250)
    The article says that the caps have "... a letter "X" stamped on the top." They are not stamped with the letter "X" - they are stamped to allow the caps to deform and vent the boiling liquid contents in a predictable manner when it fails. That is why the top of a failing cap bulges and not the sides.

    Not that it always works - plenty of caps still just "pop" violently and spew their content across the electronics anyway.

    So don't look for a stamped "X", chances are all your caps have them ..
  • > "but the article also discusses what to do if you suspect you've got a case of the bad caps."

    Anyone else misread this as "what to do if you suspect you've got a case of the bad clap [sexinfo101.com]"?

    Sheesh, I've got to start reading the headline first (although on /. that doesn't always clarify things either).

  • The real story is in IEEE Spectrum, April 2003 (Score:5, Informative)

    by Animats ( 122034 ) on Friday November 11, 2005 @01:58AM (#14005404) Homepage
    The capacitor story is covered properly, with manufacturer names and electrolyte formulas, in IEEE Spectrum for April, 2003. But you have to be an IEEE member [ieee.org] to read it.

    The definitive study, from The Computer Aided Life Cycle Engineering (CALCE) Electronic Products and Systems Center [umd.edu], is "Identification of Missing or Insufficient Electrolyte Constituents in Failed Aluminum Electrolytic Capacitors" [dfrsolutions.com]. CALCE actually took capacitors apart and analyzed the electrolyte.

    To see if the excessive hydrogen was being produced by impurities in the capacitor foil, wavelength dispersive x-ray spectrographic (WDS) analyses of foils from a capacitor from the lot of Taiwanese capacitors known to bulge and foils from a capacitor from a lot of non-bulging Japanese capacitors were performed.

    A small amount of magnesium was detected in both the Taiwanese and Japanese foils, and copper was detected in the Taiwanese foils alone (see Table 1). Ignoring the topical constituents of oxygen and carbon, the purity of the cathodic aluminum foil from the Japanese capacitor worked out to be approximately 99.1 wt%, which was within the limit set by Dapo. The purity of the cathodic aluminum foil from the Taiwanese capacitor was approximately 97.5%,which was below the minimum value stated by Dapo. The insufficient purity of the Taiwanese aluminum foil could cause gaseous hydrogen production that would not be impeded by a depolarizer, but the galvanic couples were not thought to be sufficient to account for the rapid production of hydrogen gas that was necessary to cause the relatively rapid bulging of the capacitor cans. There were other anomalies in the ion chromatographic analyses,chiefly variations in the amounts of ammonium and phosphate ions present. Ammonium ions in water form ammonium hydroxide, which is strongly basic. This raised concerns about the pH of the electrolyte in the bulging capacitors,as a review of the chemical properties of aluminum oxide - the dielectric - showed that it is slightly soluble in basic solutions (but not in acidic)[8 ]. Measuring the pH of electrolytes from capacitors from the Taiwanese lot known to bulge and from a Japanese lot that had not exhibited bulging showed that the electrolytes of the bulging lot were weakly basic (7 < pH < 8),while those of the non-bulging lot were acidic (pH 4).

    And that's the cause - internal corrosion because the electrolyte has a highly acidic Ph.

    • Re:The real story is in IEEE Spectrum, April 2003 (Score:2, Informative)

      by Anonymous Coward
      Uh, the *good* ones are acidic, while the *bad* ones are basic. BTW, aluminium is amphoteric - it is attacked both by bases and acids. That's also one of the reasons it is good electrode material.
  • It's not just motherboards that are affected - I've lost a couple of nVidia GeForce4Ti's that way.
    It's now gotten to the point where I have to specify motherboards and graphics cards without GSC capacitors. Every single Gigabyte GA-7VRXP we've had has had bad caps develop over two years - three happened in the space of two weeks, just after the warranty expired of course!

  • Allow me to get my asbestos suit on, because I know this is going to piss some people off, but whatever.

    Anybody who's been a hardware tech and built machines for any significant length of times, has known about issues like these for years. And the funny thing is, a lot of people wind up blaming Windows on problems that were really being caused by faulty hardware. In the early days of win 95, I noticed a lot of times that Windows was really unstable due to low end and sometimes bad hardware. Granted, windows

  • Bad caps turned the iMac G5 into a lemon (Score:3, Informative)

    by pvera ( 250260 ) <pedro.vera@gmail.com> on Friday November 11, 2005 @02:14AM (#14005471) Homepage Journal
    We bought six identical iMac G5s, plus two of us bought identical systems for our homes. Out of the batch of 8 machines, we have:

    1. Replaced the motherboard in two of these machines.
    2. Replaced burned power supplies in one of these.
    3. A third machine burned both the motherboard and the power supply. It has taken Apple over a week to ship the parts to be replaced.

    Al repairs so far have been under warranty. Half the service transactions have been done thru the genius desk, half thru Apple Care. Both methods are painfully slow.

    Also, on the iMac G5 Apple will extend coverage specifically for the capacitor issue, so even if your warranty coverage expires they will fix your machine at their expense (http://www.apple.com/support/imac/repairextension program/ [apple.com]).
  • I had a mobo from Gigabyte with some bad caps a while back. The board had lasted a couple years, and at one point I ended up putting it in a machine to put in my lab on campus. I knew there was something wrong with the caps, because the tops of them had sort of bulged open, and a bit of the electrolyte had leaked out and crusted on them. But since the board seemed to work fine even in that condition, I didn't worry about it.

    A few weeks later, I was unable to connect to the machine from home, so I went do

  • That's right, business as usual. It's not just motherboards, it's nearly every type of componant. I've seen motherboards, power supplies, and monitors blow capacitors, too.

    You have to remember, (A) by the time the caps have blown, the products are usually well out of warranty, and (B) the percentage of customers who will ever know that you used cheap capacitors is next to nil. That doesn't give you much of an incentive not to use the cheap ones, does it?

    steve

  • People still forget... (Score:2, Informative)

    by Trogre ( 513942 )
    ... the most important thing to remember when buying Dell computers:

    Don't

  • Capacitors are a fact of like when it comes to electronics.
    they go bad in TVs, Computers, even your clock radio.

    thing is, we demand bigger and better and the power requirements are getting higher and higher.

    Processors are getting faster and faster and that demands absolutely clean power.

    I had 2 motherboards fail 2 days ago (how ironic)
    Recapped with low ESR, hitemp caps and im good to go for at least another couple years.

    Some of these caps are cheap, dont get me wrong.
    Expecially on motherboards. but motherbo

  • i had one (Score:3, Interesting)

    by Keith McClary ( 14340 ) on Friday November 11, 2005 @04:21AM (#14005948)
    i had one in a standard el-cheapo power supply. impressive bang, cloud of white smoke, box full of cap shreds.

  • Don't replace caps unless: (Score:4, Informative)

    by Ancient_Hacker ( 751168 ) on Friday November 11, 2005 @09:05AM (#14007062)
    Please don't try replacing bad capacitors unless:
    • You're really sure you have bad capacitors.
    • You have successfully removed capacitors from a board before.
    • You have the right tools:
      • A fine-point soldering iron, 47 to 150 watts. NOT your typical 20-watt pencil iron.
      • A solder-sucker.
      • Known good capacitors:
        • Not from Rat-Shack.
        • Not salvaged from a dead car stereo
        • Same uF.
        • Save Volts
        • Rated for HIGH RIPPLE CURRENT.
        • Rated for 85 or 105 degrees C.

        (Best bet is to order them from Digi-Key, they list the full specs.)

      • A grounding strap for your body and soldering iron.
    • Willing to take the 25% risk of killing the mobo anyway.
    The reason for all these cautions is that mobo power supply capacitors are highly stressed-- those square black FETs are hitting the caps with 30-amp pulses about 200,000 times a second! Your basic Radio-Shack 49 cent capacitor can't handle this kind of stress.

    You also need a big honkin' soldering iron as each of those capacitor leads are soldered to many layers of copper foil, which make excellent heat sinks. It takes 50 to 100 watts of heat to heat up all those layers in an expeditious fashion.

    I would first practice this art on an old scrapped motherboard. A true geek always has a few of these around. Practice your unsoldering technique until you can get a capacitor off (no jokes pls) in 20 seconds with no damage to the board.

    Don't ask me how I learned all the things not to do.

    Anybody want to buy a few "as-is" mobos?

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