At the office, we get new high-end computers every three years.
The last batch of Dell GX-270s, several of us had to have the
motherboards replaced
due to bulging electrolytic capacitors. Fortunately, none of them went
out with a bang.
The symptom? Sudden reboots that weren't requested.
73 de Jim - AD6CW
Dr. Gerald N. Johnson wrote:
> Some varieties of miniature electrolytics have a high power factor when
> new and fresh. Many were not well made. There was once a period when
> nearly every computer mother board had bad capacitors because some
> Chinese lowest price maker didn't make the right and they couldn't stand
> rated operating voltage or even a fraction of it. But tended to short
> and eject their guts.
>
> I've been testing miniature electrolytics for several years with a
> modified Heathkit capacitor tester that has power factor on two of the
> capacitance ranges. I've found no used miniature electrolytics with good
> power factor and the most commonly available new ones not better. The
> low ESR and high temperature range capacitors measure significantly
> better.
>
> I'm of the opinion that in time, if not now, many solid state vintage
> radios need every miniature electrolytic replaced, just like we replace
> molded oiled paper capacitors for their inherent leakage. And like those
> oiled papers, I don't think its worth the bother to test them, just
> replace them. Even the low ESR parts aren't expensive.
>
>
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