Overrated Capacitors?

[willawake]

Re: Overrated Capacitors?

tantalum i did not see for a few years.

there is also rubycon pc-con polymer caps
http://www.rubycon.co.jp/en/pc-con/index.html

[willawake]

Re: Overrated Capacitors?

going back to the topic of ripple current affecting lifetime of caps. How does throwing a UPS into the equation figure. generally i have found good caps in UPS systems. or do UPS not really filter to the level we are interested in.

[stretch0069]

Re: Overrated Capacitors?

is it possible that low quality psu can affect cap lifetimes on a motherboard.

Way back when I first had trouble with my VP6, it was recommended that my PS was screwy. I replaced it with a higher rated Antec (I think....I hate getting old) and it ran fine for a couple months. Then the old problems came back. I replaced the caps on the MB and all was well.

So I would have to say that yes....a bad PS can cause more problems.

[PeteS in CA]

Re: Overrated Capacitors?

did you test any panasonic?

Yes. I've gotten inconsistent results with FC, excellent in one voltage/case, poor in another. With FM, I've had less experience, as the max voltage for the series is 50V. That said, the FMs I've tested have performed very well. With the three 'Cons and Panasonic/Matsushita I do not at all doubt the ESR, Ripple Current, or life ratings. What I'm observing is how they perform under abuse.

is it possible that low quality psu can affect cap lifetimes on a motherboard. how does eliminating caps from the original design for cost savings affect also.

Yes. The ripple current is going to be about the same. With crap caps in the P/S, MB caps on the same line may see increased ripple current. In the same way, if a cap is eliminated, whether thru not installing or failing, that will increase the ripple current thru the remaining caps (IOW, when one crap cap fails, it hastens the failure of those that remain.)

[PeteS in CA]

Re: Overrated Capacitors?

I don't know whether anyone here has heard of this discussion board, but they have an Apple crap caps thread.

[PeteS in CA]

Re: Overrated Capacitors?

Tantalums are dry electrolytic - that's their major feature, apart from compactness and low inductance. They do fail occasionally, but usually only due to overvoltage, reverse polarity and humidity seeping through cracks in the epoxy coat.

Some tantalums have liquid electrolyte - very acidic IIRC. Tantalums also may fail suddenly and dramatically due to ripple current and ripple current surges.

[RJARRRPCGP]

Re: Overrated Capacitors?

which boards are you talking about? the g5 has the most caps i have ever seen on a board.

Pre-2003 socket A motherboards seem to have the most caps of 1000uf and higher.

[Chris1992]

Re: Overrated Capacitors?

RJARRRPCGP: I had a PCChips M810LMR board, same as ECS K7SEM. It had 10 caps in just the VRM section. Rather weird for a low-end mATX board. I think the 'most caps' award goes to Abit BE6-II though.

[Rainbow]

Re: Overrated Capacitors?

I think the 'most caps' award goes to Abit BE6-II though.

"They're crap and cheap so at least we put a lot of them there".