How is it possible to establish bad becoming good?

[davmax]

I would like to know how we can tell if we are not missing out on perfectly acceptable caps.

Yes Taiwanese and possibly main land China manufacturers used a wrong formula years ago and many older PCs have been collapsing. I am certain that these manufacturers have taken action to remedy the problem or they will have no market. China is developing at a screaming rate and technology advances are certainly rapid also.

Have you bought a digital camera or other technologically advanced product made in China? Is it better than you expected? Probably the answer is yes, because most such products are controlled by expertise external to China. Most manufacturers are having controlled production in China. To keep costs competitive it is also possible that cap brands external to China are in fact having their product made in China. Typically the host country (China) will then acquire the technology and produce their own brand. History tells us that this happened in Japan.

We are naturally very cautious about caps from China. At some stage many manufacturers will be producing really good product. Surely we do not want to wait say five years to find out that we have been missing out. What procedures are in place to check product quality so that we can take benefit of good low cost product?

Note. The nature of an electrolytic is that they all fail in time, just a matter of how long will this be. I have just replaced all the Nichicons in a FAX machine that is a about twelve years old and runs quite hot. The caps got to their use by date.

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[PCBONEZ]

Re: How is it possible to establish bad becoming good?

Reviving an old thread I guess but I've been wondering the same thing for months.
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One of the major problems with caps from Taiwan and China is the low quality of the aluminum used in the foil and cans. - Lacking a lab facility I don't know of a way to check that.

Perhaps the best we can do is a series of surveys such as:
"What is the NEWEST board you have found bad Teapos on."
"ACTUALLY BAD, not just preemptive replacement."

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[hardwareguy]

Re: How is it possible to establish bad becoming good?

Samxon has been excellent and as for Teapo, let me tell you about a power supply I ran into a couple weeks back.

A lady calls me up to say that her PC is noisy but otherwise fine. I come over with a case fan and I replace it. Just as I was about to leave, I noticed that it was a bit too quiet.... the PSU fan was frozen! None of the Teapo caps in this Fortron PSU had bulged or vented.

The computer is still running fine.

[gdement]

Re: How is it possible to establish bad becoming good?

Samxon has been excellent and as for Teapo, let me tell you about a power supply I ran into a couple weeks back.

A lady calls me up to say that her PC is noisy but otherwise fine. I come over with a case fan and I replace it. Just as I was about to leave, I noticed that it was a bit too quiet.... the PSU fan was frozen! None of the Teapo caps in this Fortron PSU had bulged or vented.

The computer is still running fine.

I had the same experience with a Fortron-built Sparkle 300W a couple years ago. I just recently tore it down again so I remember that the PCB date code was late 2004, something like 0444.
A couple years ago, my sister called to tell me that her computer's overheating alarm was going off, but still ran fine. I looked at it about 1-2 days later. The CPU temp was indeed quite hot according to the BIOS, but I couldn't find much wrong. Then I noticed that the outer shell of the power supply was baking hot, and the PSU fan wasn't running. I pulled it out, took it home, and replaced the fan. None of the Teapos inside showed any problems, and at the time I didn't have replacement capacitors anyway. It ran fine ever since, putting out perfect voltages.

It finally went out of service a few weeks ago due to my sister getting an upgrade. Just a couple days ago I replaced the Teapos and Jamicons just because I can. There was still nothing wrong with them or the PSU's performance. All the caps I replaced were general purpose 105C models though, not low ESR. There's 1x 3300uF 16V low-ESR Teapo inside, and i didn't have a replacement for it so it's still in there.

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I also never found any bad Teapos on any of the Epox boards I was recapping in the past. They were conspicuously always good, while the GSC and Tayehs were usually bad. When people say they have a bad Teapo, I've often been able to tell from pictures that it was actually a Tayeh (an understandable mistake). I won't try to deny that they ever fail, but I don't think it happens very often. Dare I say, their failure rate appears on par with the Japanese nowadays. It's possible Teapo has some faulty series and some which work great, and we just need more info when failures are reported so we can work out the pattern.

I still greatly prefer the Japanese brands, but when I see a board with Teapos already on it, I don't expect anything productive to happen by recapping it.

Teapo has a cheap bung seal which may contribute to drying out or getting contaminated more easily. I think the cheap packaging is Teapo's biggest problem, not their electrolyte. I can't find it anymore, but I once found a failure symptoms chart on Teapo's web site which pointed to contamination as a likely cause of failing when young without visible signs. This seems to be the failure mode people report on these caps.

[PCBONEZ]

Re: How is it possible to establish bad becoming good?

I've had bloated Teapos on motherboards but in every case I can remember the boards were manufactured between 2000 and 2003-ish. (Mostly i815 thru i845 boards.)
That puts them right in the midst of the bad electrolyte fiasco.
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So, I'm wondering if Teapo and some others have cleaned up their act.

[Azurael]

Re: How is it possible to establish bad becoming good?

My Hiper TypeR 580W PSU (circa 2006) is full of Teapos and still going strong, despite having powered an SLI 7800GTX + C2D at 3GHz, followed by the same CPU + a 2900 XT for 9 months, and now a C2Q (B3!) at 3GHz with a G92 8800GTS, which has been left running overnight running at 100% (400%?) CPU load encoding H.264 video with Handbrake fairly consistently for the last few months.

Before I swapped my case for one with the PSU at the bottom, it was removing quite a bit of heat from the case too - the fans in the PSU only ever became audible under heavy load for extended periods, so I guess it must be pretty hot inside that little box too.

[gonzo0815]

Re: How is it possible to establish bad becoming good?

I have some FSP oem PSu`s from 2004 Medion system. And yes, all the Teapos are bulged, yet the PSu have no sings of problem.

Admittedly, the PSU is made silent by compromising cooling. But from my point of view, it is nothing new, that Teapo and virtually every crappy capacitor can survive a long time with excessive cooling. Any PCP&C. PSu is proofing this.

Sourcing high quality raw material, installing an own QS system with knowledgeable people who analyse the stuff is expensive.
From my point of view, that is what makes Taiwanese capacitors a cheap seller.

It is a tool, to let the component manufacturer squeeze out their margin, after they negotiated the FOB price of their PSU´s, boards or other electronic appliance with the importers and wholesalers.
And to be honest, producing cheap is probably the only reason why such badcaps manufacturer are existent.

If we are looking at Samxon, it is obvious, that even a Taiwanese or Chinese manufacturer could produce some quality capacitors.
But not out of thin air. I think it is an conscious decision, to produce crappy capacitors for cheap, just as there is a demand for it.
From this respect, i would not say that those manufacturer are simply dumb asses, i rather think they do their best for the money they get.

[PCBONEZ]

Re: How is it possible to establish bad becoming good?

The good caps out of Taiwan and China are built with imported aluminum foil.
(Usually from Japan).
They don't need their own QS full time to do metal purity testing if they simply utilize a respectable source.
[You get a truck load of aluminum in, take a spot-check sample from each roll, and you are done for like a month or even months. An outside lab would be fine. If you've seen the rolls this foil comes in they are 2 to 4 ft wide and 3 to 6 ft high. They last a while. ]
That adds very little to the build cost if you look at the ends. (Per completed part.)
It would add a great deal more to the value and saleability (sale price) to the product than would lost by the added manufacturing expense.

"Yes, we are in Taiwan, but OUR caps are built with Japanese Aluminum!"

The reason things are cheaper from Taiwan is that the labor is cheap.

--

Samxon is a good example but they aren't a Taiwan company.
[Wrong side of China...]
Samxon is part of Man Yue Electronics Co who is out of Malaysia.
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They opened a capacitor factory in China in the mid 90's and another about 10 years later (presumably to take advantage of the low labor costs and to get themselves 'closer to the heartbeat' of the capacitor market) but they are still a Malaysian company.
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My bet is that they import their aluminum (and possibly electrolyte) from Malaysia or Japan and that's the (one) reason they have a better than average product relative to most from China.
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[Computergeek1200]

Re: How is it possible to establish bad becoming good?

I've used teapo without problems execpt for one on a dlink gigabit switch a while back 1000uF --> 56uF

[370forlife]

Re: How is it possible to establish bad becoming good?

My HEC Zephyr 750W psu's main cap is a Teapo, and it runs 24/7/365, sometimes folding on a Athlon 64x2 5000+, 4gb ddr2-800, 9800gt, and a WD 7200rpm sata hard drive.

Never had any problems, has 2 fans, one in the back and one on the bottom. Back fan only runs when the psu hits 60% load, and it has yet to turn on.