*moved to marvin*

AFAIK, that bad capacitor plague was caused because those capacitors are filled with bad formulated liquids. They were made around Athlon and Pentium 4 478 times, so Pentium II and III are not affected (they were made earlier).

A funny fact is that I've seen far more Pentium 4 motherboards with blown/fatty capacitors than Athlon... maybe that urban legend about AMD reliability is not entirely true? 😉

Keep in mind that, with enough time, any capacitor run dry and fail. Maybe it's soon for your motherboards, but old computers (=8 bit computers) often need recap.

computergeek92 wrote:

I was thinking, can I help prevent bad capacitors in my computers if I can keep the system cool enough? I want to use a Slot A Athlon K7 board, but they were not built to last in comparison to older systems due to the bad cap plague. BTW, were Pentium II and III boards not so vulnerable because they ran far cooler than Athlons?

Well, all electrolytic caps are to be considered perishable. They age chemically, the ESR gets higher, and due to that the caps start developing more heat, which speeds up the aging further. And so on. In the end, they either dry out or burst. It's not only those "plague ridden" caps from the beginning of the century, they just used a bad electrolyte formula that ages much faster than others.

In a way you're right. Later processors consume a lot more power, which means CPU VRM caps, etc, needs to handle larger currents. Of course the higher efficiency of newer components offsets this a bit, but in the end, the margins becomes smaller, and the motherboard becomes more prone to failure.

If you ask me, it's better to just recap every 15-20 years than trying to delay the inevitable.

I also seen much S462 Systems with bad capacitors.

Heat seems to accelrate the Problems with poor electrolyt capacitors 😁
I have seen more bad MicroATX Boards then normal Sized Ones with Bad Capacitors.

Zup wrote:

AFAIK, that bad capacitor plague was caused because those capacitors are filled with bad formulated liquids. They were made around Athlon and Pentium 4 478 times, so Pentium II and III are not affected (they were made earlier).

A funny fact is that I've seen far more Pentium 4 motherboards with blown/fatty capacitors than Athlon... maybe that urban legend about AMD reliability is not entirely true? 😉

Keep in mind that, with enough time, any capacitor run dry and fail. Maybe it's soon for your motherboards, but old computers (=8 bit computers) often need recap.

Have seen plenty of P2 and P3 motherboards with bad caps... even some SS7 boards.

Heat accelerates the decline of capacitors, so assuming the chemistry of the capacitor is basically sound then running them cooler will help them last longer. However, many of the notoriously bad caps have such defective chemistry that they fail and bulge in a matter of time even if they've never been powered in their lives.

I wonder if it would be better to leave retro systems on 24/7 with good cooling and circulation, or keep them powered off when not in use? I tend to keep them powered off because I only use them maybe an hour a day on weekdays and a few hours a day on the weekends and holidays.

Recap with polymer capacitors. These will last longer and have ultra low ESR.

Zup wrote:

AFAIK, that bad capacitor plague was caused because those capacitors are filled with bad formulated liquids. They were made around Athlon and Pentium 4 478 times, so Pentium II and III are not affected (they were made earlier).

A funny fact is that I've seen far more Pentium 4 motherboards with blown/fatty capacitors than Athlon... maybe that urban legend about AMD reliability is not entirely true? 😉

Keep in mind that, with enough time, any capacitor run dry and fail. Maybe it's soon for your motherboards, but old computers (=8 bit computers) often need recap.

Wheren't there also bad caps around in the early 90s ?
I heard that the handheld consoles from Sega had them installed.

Another thing I also remember:
Back in the middle of the last century, germanium tranistors like the once popular OC170/AF117 series
were "infected" by a unknown desease. Some people say it was caused by a bad filling, which
caused the growing of "hairs" on the bottom of the transistors.

Source: Transistor Faults, Testing and Replacement

The best thing you can do to help prevent bad caps or at least extend their life is to use a great PSU. Everything in front of the PSU will be stressed more if the PSU can't deliver clean power. Get yourself a great quality brand such as Seasonic, FSP/Fortron, Sparkle, others as well, but you get the idea.

Since we are dealing with vintage hardware, even some of those high-end brands were affected by the plague, others are simple old and should be recapped for freshness sake. But the point is that their circuitry topology is superior to typicbrands such as Antec, Thermaltake, etc. Although, those brands do make more-than-adequate supplies when recapped with quality capacitors.

Logistics wrote:

The best thing you can do to help prevent bad caps or at least extend their life is to use a great PSU. Everything in front of the PSU will be stressed more if the PSU can't deliver clean power. Get yourself a great quality brand such as Seasonic, FSP/Fortron, Sparkle, others as well, but you get the idea.

Since we are dealing with vintage hardware, even some of those high-end brands were affected by the plague, others are simple old and should be recapped for freshness sake. But the point is that their circuitry topology is superior to typicbrands such as Antec, Thermaltake, etc. Although, those brands do make more-than-adequate supplies when recapped with quality capacitors.

Agreed. And it is even better if you do also combine your psu with some kind of line filter or surge protector.
They are available in different size and shapes and are sometimes built into power outlets (multi-outlet power strips).
https://en.wikipedia.org/wiki/Line_filter
https://en.wikipedia.org/wiki/Surge_protector

In additions, an absolute must have is a Residual-current device.
It immedialy cuts power in case of a short-circuit (faster than a fuse does).
The better ones do also include an overcurrent protection circuitry.
Nowerdays, both circuits can usually be found in the fuse panel.
Except maybe in countries with a moribund or archaic power supply system (US, maybe ?)
https://en.wikipedia.org/wiki/Residual-current_device

And if your'e a fan of old TV sets, an isolation transformer can be helpfu, as welll.
https://en.wikipedia.org/wiki/Isolation_transformer

Sorry for the bad explanation. But these devices are worth considering, because they can safe lives.
At least the quality ones. It doesn't help to buy a cheap power outlet with a filter,
if the power outlet itself causes a fire.

Oh and there's another important thing to keep in mind.
Older devices were made for a lower voltage. Back in time, devices were designed to be used with 110v and 220v systems of that time.
Nowerdays, voltage increased to 140v and 250v. Old transformer based apparatuses can't handle this. They might break or catch fire.
Yeah, I know, it sounds absurd, but I've seen it myself. My father's record player passed away this way, for example.
If you worry about this, you may want to consider to use step-down converters. Btw, this issue is also present if you're trying
to use japanese 100v devices on the american 120v lighting mains.
http://www.japan-guide.com/forum/quereadisplay.html?2+13241
http://www.voltagetransformers.com/categories … pan-Converters/
http://assemblergames.com/l/threads/120v-to-1 … n-the-us.47124/

Jo22 wrote:

In additions, an absolute must have is a Residual-current device. It immedialy cuts power in case of a short-circuit (faster tha […]
Show full quote

In additions, an absolute must have is a Residual-current device.
It immedialy cuts power in case of a short-circuit (faster than a fuse does).
The better ones do also include an overcurrent protection circuitry.
Nowerdays, both circuits can usually be found in the fuse panel.
Except maybe in countries with a moribund or archaic power supply system (US, maybe ?)
https://en.wikipedia.org/wiki/Residual-current_device

While I agree that an RCD is helpful to avert disaster, it is only because it will trip in more situations than a regular breaker. Fault current limiting requires a device like a current limiting fuse. They will also typically limit fault currents into the range of kiloamps. Furthermore, no interrupting device immediately interrupts current. They all have operating and clearing times which reduce as fault current increases, but they never become zero.

Apologies for being pedantic, but this is a mistake that is often made by electricians and even electrical engineers.

gdjacobs wrote:

Apologies for being pedantic, but this is a mistake that is often made by electricians and even electrical engineers.

Nah, that's perfectly fine what you said. So thanks for your reply and pointing this out. ^^
In my post I simply meant a very short amount of time, as you have guessed.

So I suppose the vintage boards with solid caps or those small yellow square ones with last much longer.

computergeek92 wrote:

So I suppose the vintage boards with solid caps or those small yellow square ones with last much longer.

If your talking about Tantalum Capacitors. They last pretty long but if they fail it can be a catastrophe. Some of them short out taking out other things. The typical Electrolytic capacitors open instead of short a circuit as they fail.

Electrolytic capacitors have been a problem since forever it seems. In Mitsubishi TV's (and others) from the last 80's to the first half of the 90's used inferior capacitors that would leak Electrolyte and cause Damage to the copper traces on Circuit boards. I even have a 1992 Dodge Stealth (Mitsubishi 3000GT) that had the same problem leaking electrolyte on the ECU board that caused all kinds of problems.

Hell, I have fixed quite a few newer computer wifi routers that use crappy capacitors in the power adapter and on the main circuit board. Anywhere a Manufacturer can cheap out they will do it.

Even good Electrolytic caps will fail with time. For older Pentium/Athlon and earlier boards I would just replace them with a known good brand of caps and use a good high quality power supply from there on in. I've thought about Poly caps but for the price and effort you can fix alot of other parts.

Jo22 wrote:

Wheren't there also bad caps around in the early 90s ?
I heard that the handheld consoles from Sega had them installed.

There have always been bad capacitors around, but there was a particular plague of them in the early 2000s when electronics manufacturers started finding cheaper sources of low ESR caps in China. Most of those turned out to have such defective chemistry that they were virtually guaranteed to start leaking in ~2 years. By the time it all started to hit the fan, many motherboard and PC manufacturers were in so deep with those caps that it was a catastrophe.
The most famous backstory behind many of those caps was an electrolyte formula that somebody stole from one of the reputable Japanese manufacturers. It turned out that formula was incorrect. It got spread around widely through the dodgy no names in China.

Using a quality power supply is good for your hardware, but I don't think junk caps can be kept going no matter what you do. Many of them are so unstable that they will fail just sitting there. Try to find a P3 ABit board with Jackcon caps that haven't bulged - I seriously don't think any exist.
Eventually they just have to be replaced, and it's better to do it before they fail so they won't cause collateral damage as they die. Motherboards aren't the easiest thing to solder, but practice on some junk boards and it can be learned. Once you have reputable caps installed then preservation is more feasible. Just avoid letting them get super hot and ideally try to power them up at least occasionally.

computergeek92 wrote:

So I suppose the vintage boards with solid caps or those small yellow square ones with last much longer.

The small yellow square caps are tantalums. They are very reliable if they are powered on a regular basis. But if they sit around for several years, there is a significant chance that they will explode. It's exciting when it happens, they spark and bang like fireworks.

How can I tell the condition of tantalum caps? Quote: "Some of them short out taking out other things."

It looks like based on the info in this thread I have now realized that it was a failed black tantalum cap that killed my MSI K9N2 Diamond motherboard. It was a regularly used system but one day I smelt smoke coming from the computer. The black tantalum cap burnt out and caused some black soot to appear on the board. Six months earlier my PCIe sound card in the slot near the failing cap had wishy-washy performance. It could've been due to the bad cap. I threw the board out, but it was surprisingly working just fine as the cap was smoking out. Good thing I detected the problem in time. Could I have saved and fixed the board had I knew what the problem was earlier? Can a tantalum cap be replaced with a solid cap or other kinds of caps?

Bad tantalum caps are fine, as far as I know. At least until they literally EXPLODE. (no joke)

Now I’m kinda afraid of using tantalum based parts.. They are very common on just about every computer component, even some hard drives! 😲