They lasted about 6000 hours - we could set it in a calendar and did so many RMAs. For the local 911 center, we'd replace the boards every 4 months, before the caps failed, because they just couldn't tolerate the downtime.
Only later did I learn that it actually seemed to have been industrial espionage gone wrong! https://en.wikipedia.org/wiki/Capacitor_plague
That's probably also the reason why so many retro enthusiasts just generally "re-cap" almost everything they touch. In a lot of cases, you just don't need to do that, and sometimes it could be worse to replace capacitors not affected by the capacitor plague: Any factory adjustments made to the device could well depend on the exact characteristics of the capacitors that were present in the device when it was manufactured.
This is one reason mining GPUs can be a questionable buy. The miner may have operated them at "low" temperature, but they were on 24x7, whereas a gaming PC may be only on a couple of hours a day a few times a week.
Ultimately it comes down to how much the designers overspec'd components and/or factored in for wiggle room and how much the capacitors can degrade before circuits start acting up enough for the user to notice.
Never met such a gamer
It also depends on how exactly the caps are used. Caps close to a massive heat source, like a power resistor, are likely to dry out relatively quickly, while others, like those used as part of small signal filters, may last literal decades, with not much change in e.g. ESR or capacitance (and hence still conform to factory calibration pretty okay). Admittedly I don't have any hard data for that, only anecdotical experience with measuring ESR and capacitance and saying "this looks fine".
The crucial point is that the "capacitor plague" affected much more than products which were on 24/7 or which had tight tolerances, to the point where it was very well visible to the "casual" consumer. Yes, we may not expect a server mainboard that was on for the last 20 years to still have its caps within spec, but wrt the capacitor plague, the gaming PC you mentioned would have been quickly affected, in an obvious manner, as well.
I wouldn't expect those to be electrolytic, though. Electrolytic capacitors are mostly used when the exact characteristics are not important, like on a supply bus, where your qualifications are typically either "at least" or "no more" than some value. Tripling capacitance usually has no negative effect on a supply bus but huge change of doing signal conditioning, so something like that is more often going to be a capacitor that is intrinsically more stable.
Wait, how many of these are in a typical consumer computer? Even if it's just 20 or so (I truly have no idea) I don't get the numbers to add up.
I've run, say, 6 computer-years worth of capacitors with no problems -- under the assumption above this would be 120 capacitor-years. Let's say at this point there's a 50--50 chance I would have experienced problems (this is not a rigorous survival analysis, of course, just something to get started).
If a single capacitor has a lifetime of just one year, then "lifetime" must be defined as the solution to p^120 = 0.5 which is p=99.5 %. Is it correct that when one speaks of the "lifetime" of capacitors one refers to the point where 0.5 % of them no longer work?
If "lifetime" means 50 % no longer work then I would seem to have been extraordinarily lucky (I'm the 10^-35 %!!) -- I don't hold that for very likely.
What else am I missing?
Capacitors especially and in general most components age and their specs drift. This is not a valid reason for not replacing components. If something isn’t actually all that old, sure, but capacitors especially are just not precision components over long periods.
More generally however, you just don’t need to replace a capacitor in something that works well and that is not anticipated to break catastrophically because of the capacitor plague.
If the caps do eventually drift off so far that it affects operation, replace it then, and then it makes sense to take the opportunity to replace others as well as precautionary measure.
Sometimes you know that a non-plague cap will likely fail because it’s right next to a massive heat source, and you may replace it early with good reason.
But sometimes I see people literally replacing 80 caps or more without reason, when I have the same device sitting at home with its original caps, still doing its job well within spec for years.
The relevant bit from Wikipedia:
> Industrial espionage was implicated in the capacitor plague, in connection with the theft of an electrolyte formula. A materials scientist working for Rubycon in Japan left the company, taking the secret water-based electrolyte formula for Rubycon's ZA and ZL series capacitors, and began working for a Chinese company. The scientist then developed a copy of this electrolyte. Then, some staff members who defected from the Chinese company copied an incomplete version of the formula and began to market it to many of the aluminium electrolytic manufacturers in Taiwan, undercutting the prices of the Japanese manufacturers. This incomplete electrolyte lacked important proprietary ingredients which were essential to the long-term stability of the capacitors and was unstable when packaged in a finished aluminium capacitor. This faulty electrolyte allowed the unimpeded formation of hydroxide and produced hydrogen gas.
I sometimes wonder, how those secret sauces can remain so secret. After all, you have to order them in rather large batches every week, month, year..
E: I can't believe something so easy to Google is being downvoted as though it's false info: https://www.reddit.com/r/retrogaming/comments/ib7nyh/replaci...
People would come in saying their PC didn't work. He would pop it open, take out the motherboard, go "ah yes, puffy caps. See right there", then open a drawer full of recycled capacitors, and desolder the bad ones and resolder correct ones back on. And it worked!
The shop ultimately closed but I still think back to that and a few other tricks as especially impressive.
yeah, sounds about right. i was also working in a repair shop around the same time, and we knew that we could repair the boards for our customers. but we also knew that we couldn't get away with charging enough to cover the cost of parts and labour unless we offered a warranty, and we couldn't reasonably offer a warranty on old motherboards.
we did make pretty good money selling upgraded new computers to the people whose capacitors had failed. it always felt a bit dirty to sell somebody a new $800 laptop when their old computer was repairable, and i'm sure dell was doing even better than we were on that racket.
The fact that you "get away with it" is only possible if you offer such a needed service, that people are willing to pay.
If you want to be charitable, leave some money on the table for customers who look in dire straits. But you should not feel bad for making a profit (at least until you find yourself buying politicians).
When I was a student friends and relatives would give me (nice) broken electronics that they were going to throw out anyways, and if I liked the item (e.g. an expensive camera that I couldn't afford) I would put a lot of effort into fixing it.
> but we also knew that we couldn't get away with charging enough to cover the cost of parts and labour unless we offered a warranty
I'm not sure about that. The store charges more than enough to cover it and still gets more business than it can handle while still providing a free warranty for 6-12 months.
I.e., broadly speaking, like lightbulbs.
Wouldn't be surprised if there's a class action, where everyone gets $5 off a new printer.
Any company can get scammed on crap parts, either because they took a gamble trying to save a few cents or because those parts were all they could get their hands on, but now that's come back to bite them it's up to brother to put things right. It'd be shame for brother to trash their brand over a batch of bad capacitors. I've been happier with my current printer than any printer I've had since I got rid of my old dot matrix Epson, but we're going to need a new printer eventually, and I'd really like to not have to think too much about what brand to get or recommend.
It's true, though in the latter case, it can't be helped.
I worked at an integrator from 2002-2005. Small outfit, building PCs and servers for businesses and local agencies. As a new member of their engineering department, one of the first issues we got asked to investigate was to look at heightened failures of network cards. Back then, we bought the ubiquitous 3Com 3C-905. All of our PCs were subjected to a battery of functional tests before shipping, and we were finding that an abnormal number of the cards were failing.
We started looking at the failed ones more closely, and found them running extremely hot. These were passively cooled cards, and didn't need a heatsink under normal conditions. But on any of these, you couldn't hold a finger against without burning yourself. Functional ones as well.
We got the batch of serial numbers, and send them to 3Com to ask what might be going on. And the answer we got was that they didn't exist.
A bit of back and forth between 3Com, the distributor (a well-known and established company) and ourselves led us all to believe that they were a counterfit batch that entered the supply chain. We tracked down all of the cards from that order, and opened up every boxed PC that was to ship with one (I'll never forget the company president with his business shirt sleeves rolled up and a box cutter in his hand. He set the tone) and we pulled out every one.
We sourced from reputable places, and I don't recall another instance of that occurring while I was there. But it was an interesting event in my career, and one I'll never forget.
I commented it on HN [1] not long ago and people said I was spreading conspiracy theory.
And how it used to be a thing called capacitor marketing [2] and how Apple / Mac "used to " set itself apart.
And let me just say this again because somehow the act of understand electronics is completely lost on modern days internet or more like in the West, planned obsolescence is still a thing and just because they aren't as bad as they were ( 6 months or at best 12-18 months ), doesn't mean they are not doing it. And more often than not, it is still the same old capacitor trick 20 years later.
Edit: And some comments below are writing just about that.
The only capacitor manufacturer that comes to mind now is Kemet and their wikipedia page doesn't mention the episode so I don't know.
4 months is 2920 hours, which is less than the stated 6000 hours to failure. Though only by 2x.