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The Capacitor Plague

deadprogrammer.com

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Re: The Capacitor Plague

#41

Post by noonespecial »

reedlaw wrote: post #23

So, for hardware manufacturers, is there any reliable way to identify good quality caps?

Test them under ridiculous load. 120% of peak voltage, huge ripple, let them get nice and toasty. The bad caps will pop in minutes, a good one can survive for weeks.

The problem is that the prototypes you get from your Chinese manufacturer will be made with top quality Japanese components. They'll switch them for the cheap junk later while you're not looking, about a 10th of the way into your 1 million unit production run.

Re: The Capacitor Plague

#42

Post by tomjen2 »

ghshephard wrote: post #24

For about 6-9 months in 2006 We had a series of Dell Optiplex GX 270s that had a remarkable failure rate - close to 60% of our systems failed. We knew that Dell must have been having a tough time, when the FIRST question they asked on a support call was whether we saw any "Bulging Capacitors on the Motherboard" - I mean, not "Have you Tried Rebooting", or, "Have you tried powering down for 90 seconds", but "Do you ha…

That is all fine that Dell fixed it so fast, but had that happened to me, I would not have been using Dell in the future.

Re: The Capacitor Plague

#43

Post by ghshephard »

joe_the_user wrote: post #28
ghshephard wrote: post #24

For about 6-9 months in 2006 We had a series of Dell Optiplex GX 270s that had a remarkable failure rate - close to 60% of our systems failed. We knew that Dell must have been having a tough time, when the FIRST question they asked on a support call was whether we saw any "Bulging Capacitors on the Motherboard" - I mean, not "Have you Tried Rebooting", or, "Have you tried powering down for 90 seconds", but "Do you ha…

How did they fix a hardware failure in 4 hours? Telekinesis? Teleportation? Is there something I'm not understanding?

You just call them, and they separately courier-ship parts to you and send a technician onsite.

Go buy a $984 3 Ghz 2 Gbyte Dell Optiplex 780, and, for an additional $216, you get 3 Year 4HR 7x24 Onsite Service.

And yes, I've called them at 11:00 at night. :-)

Re: The Capacitor Plague

#44

Post by pbhjpbhj »

aaronblohowiak wrote: post #18
pbhjpbhj wrote: post #17

I assumed that they were carefully designed so that the electrolyte would go off just out of warranty (no I'm not kidding) and force a resale. Perhaps electronic manufacturers that are big enough could have a state mandated "cost of parts and actual labour costs" repair service.

actual labor costs quickly make repair more expensive than replacement.

Yeah, call out charge for washing machine repair is around £100 (minimum), actual cost is travelling 14 mi (at most where I am)@ 50p (that's the reclaimable amount for mileage) plus the "engineer's" hourly amount for perhaps 2 hours (I'm going with £25 per hour gross). So not £157 but £57 - the company absorbs the downtime costs of callout personnel - this would make a whole heap of difference in whether it is worth repairing ones washing machine.

Re: The Capacitor Plague

#45

Post by pbhjpbhj »

jrockway wrote: post #33
pbhjpbhj wrote: post #15

Earlier quoted context omitted.

A friend has an Apple iMac G4 that they paid a shed-load of cash for and expected to last well - it nearly made 3 years. The point of failure? Electrolytic caps in the [overheating] graphics card. The card is soldered in on the screen side of the mobo.

I think this is a known issue that Apple will fix, however. I remember reading something related to Apple fixing bad caps in iMacs, anyway...

They did change the caps from what I've read (there was a court case about it in the US I gather) but the real fix on teh iMac was putting ventilation holes in! Who'd have thought. Damned form over function. Also I gather they use slot mounting GPUs now?

Re: The Capacitor Plague

#46

Post by eru »

jrockway wrote: post #32
pasbesoin wrote: post #4

Earlier quoted context omitted.

Marginal (although not always illicit; sometimes just marginally spec-ed) capacitors have long been an issue including in consumer electronics. As an example, the Mac Plus power supply was notorious [well, at least if you were repairing them] for failing. Some people put out instructions for upgrading it by replacing a subset of components including IIRC certain capacitors. I've also read accounts of people improving…

This is indeed true. Some (all?) amp designs place resistors and capacitors in the signal path. This distorts the sound. For one channel, that would be fine, since the distortion is usually just a phase shift that you won't notice. (Play a song. Then play a song but start it 1ms after you were planning to start it. It will sound fine both times :) The problems start to show up with stereo, though, where you have two…

> (I am not an EE, but I have built a lot of headphone amps. The sad part is how people with $1000 amplifiers often have worse components than an amp built from $30 worth of parts. Ah, the free market...)

Don't forget your monster cables. (Or what where they called?)

Re: The Capacitor Plague

#48

Post by pasbesoin »

jrockway wrote: post #34
jrockway wrote: post #32

Earlier quoted context omitted.

This is indeed true. Some (all?) amp designs place resistors and capacitors in the signal path. This distorts the sound. For one channel, that would be fine, since the distortion is usually just a phase shift that you won't notice. (Play a song. Then play a song but start it 1ms after you were planning to start it. It will sound fine both times :) The problems start to show up with stereo, though, where you have two…

Also, I now have a sudden urge to build another headphone amplifier... :)

Glad to be of service. Hmm... and since you seem to know your way around them, do you take orders?

(Another startup born on HN! ;-)

Re: The Capacitor Plague

#49

Post by jrockway »

pasbesoin wrote: post #48
jrockway wrote: post #34

Earlier quoted context omitted.

Also, I now have a sudden urge to build another headphone amplifier... :)

Glad to be of service. Hmm... and since you seem to know your way around them, do you take orders? (Another startup born on HN! ;-)

I did for a while. I am not sure I am knowledgeable enough to do a good job anymore, however.

If you are ever in Chicago, we can have beer and I will teach you how to build an amp :)

Re: The Capacitor Plague

#50

Post by pasbesoin »

jrockway wrote: post #49
pasbesoin wrote: post #48

Earlier quoted context omitted.

Glad to be of service. Hmm... and since you seem to know your way around them, do you take orders? (Another startup born on HN! ;-)

I did for a while. I am not sure I am knowledgeable enough to do a good job anymore, however. If you are ever in Chicago, we can have beer and I will teach you how to build an amp :)

Far north suburbs. I've been a recluse, lately, but maybe when things pick up for me, I'll see you at one of the HN meetings. (Didn't realize until now that you're in the neighborhood.)
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