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Old 7th February, 2008, 11:24 PM
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trodas trodas is offline
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Wink

Gizmo - whoa, whoa, whoa Carefull out there. Technology make a great leap forward in ceramics.
Quote:
ceramic capacitor that could give you 100 µF of storage would be about the size of a dinner plate and would weigh several pounds
This is a 100uF Taiyo Yuden Y5V 100uF 6.3V cap:
http://trodas.wz.cz/kondiky/cap_images/1173609032.jpg
The size is standard 1210, eg. 3,2 mm x 3,3 mm in size
You can purchase them in Digi-key, for example. A bit expensive, tough:
Digi-Key - 587-1397-1-ND (Taiyo Yuden - JMK325F107ZM-T)
But available. I have few for extreme overclocking - place them into the CPU socket

So, easy there, fella

Quote:
Consequently, tantalums are generally only used where nothing else will do.
It is also almost impossible to make a very big tantalum capacitor. While Panasonic FC elytes line end up with 15 000uF, the very same company can't produce bigger that 220uF tantal caps.
Such size is useless in Vcore regulation, for example. Not to mention the step price... So, there are more that price reasons why not use tantaum caps. Besides, good elytes like Samxon GA line or Nicicon HZ line are hard to beat performance. Not to mention price.

And it is all not that easy. For example polymers aren't any rescue at all. If I oversimplify things, then polymers shine in hi-frequency regulation only and elytes "beat the crap out of polymers" at all commonly used regulators frequency. Especially in PSUs.
Hence if the Vcore regulator use a very high frequency - polymers is the choice for obvious reasons. If the frequency is common (eg. low), then elytes are much better choice by all cases and in results and lifetime as well. Please note that guaranted lifetime of polymers are only 1 000 to 2 000 hours. For example Panny FM d12.5 cap has 7 000 hours lifetime and Samxon RS elytes even more.

So to make long story short - for vast majority of regulators are elytes best and polymers simply is not good choice at all. There is no other hi-frequency that Vcore regulators currently used even in hi-end mobos. So yes, I say that mobos full of polymers are bad design. And I have proof of this:

Asus P5K-E - exploded Fujitsu polymer 270uF 16V on Vcore imput, just right after PSU...

http://i4.photobucket.com/albums/y13..._270uF_16V.jpg

Why? Well, because user NewBeetle from Xtremesystems forums did overclock with OCZ PSU and only a 520W one, and filled with Teapo caps...
http://www.xtremesystems.org/forums/showth...ad.php?t=151968

The imput Vcore caps should be ALWAYS elytes for best result - because they filter the ripple out of the low frequency PSU regulators...!

Now about the lifetime.
Caps have a life span. However it is like 2 000 to 7 000h per type (some even more) at the rated maximal temperature 105°C and with maximal ripple. Now for each 10°C down from the rated 105°C (for the 105°C caps) does the guaranteed lifetime DOUBLE (still with maximal ripple!) Hence in the absolutely WORST case:
105°C - 2 000h
95°C - 4 000h
85°C - 8 000h
75°C - 16 000h
65°C - 32 000h
55°C - 64 000h
45°C - 128 000h
Now bear in mind, that year has only 8 544h Hence well-cooled cap has to stay alive at least 14,9 years with every parameter in limits. Caps failing in good environment in like year or two are most common. Some excellent designs with Teapos (mine ABit ST6R) make 5 years. But that is still far from what they should last.
Hence they are bad caps.

Some bad caps fail and leak even w/o actually being used. These are even inferior brands of bad caps and caps like GSC, G-Luxon and Fuhjyyu are among them. From the better side of bad caps are OST, Teapo and few others.

Yet still they are bad caps and ANY hardware that use them (especially PSUs!) will fail and in the process, will make YOUR mainboard fail. Overclocking and folding accelerate the process, but it is inevitable.

Furthermore, they did not "corrode" at all. What is happening is, that cap is made full of electrolyte. This is water with additives. Good additives prevent the water from breakdown to Oxygen and Hydrogen when current is being drawn. Bad ones - cheapo ones - did not prevent it much, so inside the cap is building a pressure. Hence bad caps start bulging and eventually it end up in explosion, because Hydrogen and Oxygen mix is extremely explosive.
Check out what happen to Space Shuttle Challenger. Yea, that was it.
Some caps just dry out, some explode at the end. Teapos usually dry out (no leaking, bulging!) and G-Luxons usually explode. That is why there are these vents for - so the force of the explosion is low and directed directly up, not damaging PCB.
Once cap explode near your face and you lose your hearing for a while, you will know that caps can be very dangerous things and it is not wise to confuse corrosion and explosion

Asia-X caps in OCZ PSU:
http://img352.imageshack.us/img352/7...soczpsuot2.jpg
User spyder from BadCaps forum.


PS. yes, polymers with lower temperatures extend their guaranted lifetime as well and they even claim that they do extend it MORE that 2x, but I did not fully believe this marketing informations.
And many polymers out there are plain and simply - fakes. As with elytes. So, it is a jungle out there. And there are just like 5 good caps brand and the rest are known to be bad caps... So, it is not like Gizmo says "That has been many, MANY moons ago, and the company that was making those parts went out of business (deservedly so)."

That was a lie, even I do wish it is true, it is not. There are like hundred (if not more) companies making bad caps and selling them under different names and brands. Just look at this discovery:

In short is says that the old-known terrible GSC caps are still out there, because: GSC = Evercon = Sacon = Capsun.
This is backed with solid evidence you can see for yourself in many and many images and caps types database, and screenshots...

It is ALSO proven by the fact, that they DO fail like the inferior GSC crap did years and years ago:

Sacon FZ caps on Magic-pro - it is a JetWay OEM:
http://i4.photobucket.com/albums/y13...on_FZ_caps.jpg
Don't let them fool you. They are NOT polymers, these are sleevless electrolyte caps, and a bad ones, I might add. JetWay do this all the time. Remember their mobos full of GSC crap-caps?

So, sorry guys for rather long post full of bad news. I think you deserve the truth, even it hurts badly. "Fun" fact: there is no PSU with good caps now in the market, except a server-grade PSUs like Zippy made.

But do not trust me, ask others with the same experiences like mine
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"I believe that all the people who stand to profit by a war and who help provoke it should be shot on the first day it starts..." - Hemingway my config - my caps
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