PCs Plagued by Bad Capacitors 335
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."
Problem's been around for awhile. (Score:5, Informative)
Not the first time (Score:5, Informative)
Slashdot - Taiwanese Capacitors Leaking, Exploding [slashdot.org]
Watch out for all the 'Geeks popping a cap in your mother' jokes.
-Eric
Happened to me.. (Score:3, Informative)
You can read the whole history of dying iMacs on Macintouch [macintouch.com].
it's not that hard to fix (Score:4, Informative)
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.
Problem Documented and Instructions (Score:3, Informative)
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.
Re:it's not that hard to fix (Score:5, Informative)
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)
Stamped with an "X" on top ? (Score:5, Informative)
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
Nothing to do with brand new high-tech (Score:5, Informative)
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.
Re:Nothin new here. Just like Car Makers. (Score:5, Informative)
The problem is that Nichicon screwed up somehow, not that Intel got burned for buying the cheapest parts.
Re:More than just Intel boards (Score:2, Informative)
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 many claims to replace the motherboard, our warranty service has also turned into something more along the lines of a three-weeks-later warranty. This really pisses us off because we paid a lot extra to be able to get stuff repaired immediately.
Personally I think that if Dell cannot replace these motherboards because of their own faults, they should still have to meet warranty expectations even if it means sending us a brand new system as close to the capacity (no pun intended
The real story is in IEEE Spectrum, April 2003 (Score:5, Informative)
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)
Re:If you don't wanna get ripped off. (Score:1, Informative)
Maybe heavier means more durable, I dunno, but I don't carry my 42" plasma TV everywhere. I leave mine in my living room, so don't care if it's built like a brickhouse.
Bad caps turned the iMac G5 into a lemon (Score:3, Informative)
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/repairextensio
People still forget... (Score:2, Informative)
Don't
Re:If you don't wanna get ripped off. (Score:3, Informative)
Re:it's not that hard to fix (Score:3, Informative)
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 caps. Also I have found PC power supplies have high quality caps in them, although bloating is also a common fault in them too (causes a lot of voltage variance - they are worth recapping)
(Meter them first of course
Also, I have found that replacing 6.3volts with 10volt caps of the same farad rating tend to last alot longer, especially when you see all of one spec bloating..
I always replace the caps in groups, for instance, I'll replace all of the 1000uf 6.3v caps even if only a couple are bloated. I use the same brand/specs to replace the groups.
Whether or not it's economically viable may be a different story, but I've had a high success rate using salvaged (metered) parts. I've not had to do a board twice.
I've noticed it's really only caps 1000uf and over that go, 1500uf 6.3v and 1000uf 6.3v seems to be the most common caps to fail. I've replaced all sorts of brands, so I personally feel it's crummy manufacturers fault choosing the wrong spec/quality caps to save 13 cents per board.
Temperature has a big play in it too though, i've noticed quite a few caps near regulators and heatsinks go. I think slightly higher voltage or quality makes sense near those areas.
Re:More than just Intel boards (Score:2, Informative)
Don't replace caps unless: (Score:4, Informative)
(Best bet is to order them from Digi-Key, they list the full specs.)
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?
Problem's been around for awhile - since the 1980s (Score:3, Informative)
Nichicon appears to be the only company manufacturing those short (~5mm high) axial capacitors, and our repair facility had to order them directly from Japan, as I wanted the 105 degree C rated caps, in contrast to the 55C rated caps that were installed in the radios. In South Florida, you could easily get in-dash temperatures over 200F: 90F air temperature outside the car, sunny day cooking the inside of the car.
Re:More than just Intel boards (Score:4, Informative)
Or better yet, wire one to the inside of a door handle and charge it up. Man, I never thought my grandma could jump so high....
If this can be lethal, please mod this post up informative.
If this is post is modded up, be careful! Doing the quoted things can kill people.
Safety first!
Re:More than just Intel boards (Score:3, Informative)
That's correct. Never, never play with charged capacitors. Except for the carraige bolt stick man and popping big ones, I was just kidding.