Solid Capacitor Motherboards Introduced

jckrbbt writes with news that Gigabyte has introduced solid capacitor motherboards in its Intel 945 chipset products. From the article: "[S]olid capacitors have a higher tolerance for higher temperatures and they also perform better with higher frequencies and higher current than electrolytic capacitors. The superior heat resistance and better electric conductivity will allow PC enthusiasts to tweak the highest levels of performance from their system without fear of excessive capacitor wear or exploding capacitors."

Dell

[Cherita Chen]

The three year average doesn't surprise me, Dell has had a multitude of problems with bad/bulging caps [com.com]

This is news?

[Anonymous Coward]

Iwill has been using them for over one year. Just check out the DK8EW or DK8ES boards. Looks more like free advertising for Gigabyte...

3 years???

[wiredlogic]

Solid capacitors also last longer with an average lifetime of 23 years compared to only three for electrolytic capacitors, according to Gigabyte

This is complete BS. A three year service life may be the norm for bootleg Chinese knockoffs of Japanese parts but quality Aluminum electrolytics can last far longer.

Comment removed

[account_deleted]

Comment removed based on user account deletion

Re:3 YEARS?

[alienw]

The little caps near the expansion slots are for power decoupling. There are usually lots of them and the loss of one will not affect anything as long as it does not short out. The bigger switching converter caps near the CPU are a critical component of the switching power supply, and losing one would definitely kill the mobo and possibly the CPU. They are also the ones most likely to explode or leak, since they do a lot more work and are exposed to much higher temperatures.

Why is this news?

[Angelwrath]

I've had a Gigabyte board with solid-state capacitors for more than 3 months now, it's based on the 965 chipset, so I was a bit confused why this article made it sound like this was a new innovation.

Not vacuum tubes...

[Kadin2048]

I'll stick to my vacuum tubes. Not only is the technology well-tested over the years, you can heat up the entire house if your computer room is in the basement.

What you really want are Leyden Jars [wikipedia.org].

Re:Mod parent up.

[PeterBrett]

I do a lot of DIY speaker building and there definitely is a difference between Film/Foil caps and electrolytics. A speaker crossover made with Electrolytic caps sounds like crap compared to one made with even the cheapest of film/foil caps.

Firstly, WTF are film/foil capacitors? As far as I am aware, the only major types of capacitors used are:

• Aluminium electrolytic capacitors (aluminium foil, tightly would in a dielectric fluid)
• Ceramic capacitors (single- or multi-layer, using EIA Class 1 or Class 2 dielectric ceramics)
• Tantalum- and niobium-based capacitors (chip or electrolytic styles)

Are you thinking of resistors? I use thin-film SMT resistors all the time...

Which part of the crossover are we talking about? Which design do you use? Do you have inductors in there? Quite a few performance issues when using electrolytic capacitors are due to an inappropriate choice of inductors, IMHO.

Also, I've got a friend who does psycho-acoustics research, and he did an interesting series of experiments a couple of years ago that indicated that systems that performed technically very well (almost perfect filter characteristics, no harmonic errors) actually were rated worse than a system that had all sorts of junk spewing out of it, when the audiophiles participating weren't told which system they were listening to...

Re:YAWN! Capacitor FUD

[splutty]

Funny, you sort of go completely past the point of the *actual* difference between ceramic condensators and electrolytic condensators, which is that one's polarized and the other isn't. They're not interchangable.

Re:FUD

[The Darkness]

how do you make a solid capacitor? Doesn't it work by keeping a charged capacitance between two nearby electrical circuits seperated by a vacuum?

You're close, but I recall from my physics classes that capacitors aren't required to have a vacuum between the plates. I just checked the wikipedia entry [wikipedia.org] on capacitors and found the following piece of text:

The capacitance is proportional to the surface area of the conducting plate and inversely proportional to the distance between the plates. It is also proportional to the permittivity of the dielectric (that is, non-conducting) substance that separates the plates.

So, if I understand that text correctly, you can create a smaller capacitor with the same capacity to store charge as a vacuum-gap capacitor by placing an appropriate dielectric material between the plates.

Re:YAWN! Capacitor FUD

[deevnil]

No, the real difference is the amount of capacitance. I wonder what a 100uf ceramic disc cap would look like, a frisbee?

Re:FUD

[unitron]

So, while my first instinct is "how do you make a solid capacitor? Doesn't it work by keeping a charged capacitance between two nearby electrical circuits seperated by a vacuum?"

Anytime you have two conductors separated by an insulator you have a capacitor, or at least capacitance.

If you put a sheet of wax paper between two sheets of aluminum foil, that's a capacitor. If you replace the wax paper with a layer of air, it's still a capacitor. If you replace the air with a vacuum, it's still a capacitor. You can even replace the vacuum with a non-conductive liquid. It'll still be a capacitor.

As long as whatever separates the two conductors is an insulator, then you've got a capacitor.

Electrolytic capacitors use stuff that's a sort of paste, or "goo", which, combined with a layer of oxidation on the inner surface of one of the conductors, makes up the insulator. "Solid" capacitors use something that's, well, solid.

If you have a further interest, Googling for "capacitor disease" may prove instructional.

Re:Average

[ArsenneLupin]

The author was even kind enough to link to reputable sources that confirm the story.

The story is pretty well-known, and has even been featured on Slashdot. Here are them links:

• The Great Capacitor Scare of 2003 [ncl.ac.uk]
• Leaking Capacitors Muck Up Motherboards [burtonsys.com]
• Illicit Leaky Capacitors Killing Motherboards [slashdot.org]

==> only error of GP: the formula muck-up was not intentional, but the thieves themselves made the error while copying it.

Re:Average

[markh1967]

For the full story see www.badcaps.net [badcaps.net]

Re:Dell GX270's

[parasonic]

Dell should start using these for their GX-270 line. I (1 out of 5 at the site I worked) have replaced a good 30 270 Motherbo--- (sorry per dell, system boards) that have video problems. All stem from bulgin and leaky capacitors. Most of these systems where between 1-2 years old (none over three).

On the GX270's, there is now a lifetime replacement warranty on the motherboards. Capacitors blow on these things, whether that is six months down the road, or four years. We got a bunch of 270's around 2003 and still have several dozen of them here at the company where I work. A few months ago, we called Dell, and they sent two boxes complete with new motherboards and return labels for the old ones.
 
As a CmpE (currently working in I.T.), I will tell you that electrolytics are absolutely fine. I have electronics from the 60's and 70's with electrolytics that hold up. If the manufacturing process is botched, something may go wrong. But you can end up with a mess also if you manfacture tants, micas, polypropylene, even ceramic disc capacitors incorrectly. "Solid" capacitors are more of a sure-fire thing, but they can fail, too.

mod parent DOWN, true but misleading

[petermgreen]

actually you can get non-polarised electrolytics too, they are often used in loudspeaker crossover circuits, i think they are basically two ordinary electrolytics in inverse series.

but anyway in most cases (especially in digital equipment like computers) capacitors are used in a way that keeps them biased the same way all the time so it doesn't really matter if they are polarised or not.

i agree with the gp that the important characteristics of electrolytics are big and slow (high ESR) while the important ones of ceramic are small and fast (low ESR).

tantalums are fairly big and fairly fast, they also have much better lifetime characteristics than electrolytics. The downside is that they are expensive and when they do go bang (tantalums are polarised) they tend to fragment into a shower of tiny hot high velocity shrapnel.

Its unclear from TFA if the "solid capacitors" gigabyte are reffering to are tantalums or some new technology.

Re:I'm sure the ...

[Ancient_Hacker]

>Firstly, gold plated speaker wire isn't gold plated to improve the capacitance or resistance properties of the wire - it's done to prevent corrosion.

Wrongo, Bub. Wire strands are usually tin-plated to reduce corrosion and improve solderability.

Nobody, but nobody gold-plates wire, even for the most demanding aerospace and military applications. I've taken apart Titan missle guidance computers, Mil-spec avionics, even old satellite guts and havent found an inch of gold-plated wire.

Now connector edges and IC and transistor leads that are going into sockets are often gold-plated. And I've even seen a very few Sprague electrolytic capacitors, MIL-spec, maybe one in a million, with gold-plated leads. But not wire.

> and tend to introduce a small amount of phase shift into whatever AC signal you're passing through them.

Wrongo again Bub. As you should know, the phase shift is proportional to the capacitance, and NOTHING ELSE. So a 100uF electrolytic capacitor will have EXACTLY the same phase shift as a polypropylene capacitor of the same value. And doubly false, as electrolytics are hardly ever used anywhere in their phase-shifting frequency range-- they're almost always used at frequencies where they're nearly dead shorts to AC and near zero phase angle. Exceptioin-- old cruddy speakers used non-polarized electrolytics in their phase-shifting range, but that's about it.

>And yes I am an electrical engineer! :D

Yep, I've met way too many EE's that don't recall the basic physical facts.

Re:3 YEARS?

[noidentity]

Power supply filter capacitors are generally added in excess so that there is plenty of margin. Losing one will reduce this margin for that area of the board, kind of like overclocking where you increase the chance of error. When you crushed the capacitor, you probably also shorted its terminals together, and when you cleaned it up, you probably un-shorted them again.

Re:Average

[Fordiman]

As an ex electrical engineer, I can say there are two things you remember about capacitors when designing a circuit:

1) If signal consistency is important to you, never use an RC oscillator
2) If you need it to last at least as long as you work there, always use a cap with a voltage of ceil((inputSignal.average+inputSignal.stddev*3)*1. 25)

These ifs are usually rhetorical; you always want signal consistency, and you always want it to last as long as you can be held responsible for it. Period.

Re:YAWN! Capacitor FUD

[Bassman59]

Let's be pedantic here.

You basically get three major types of caps on motherboards, each of which have different properties:

Ceramics. Small and fast. Typically used for decoupling (small charge storage).

Also used in filtering applications ...

Electrolytic: Larger and slower. They are slower because they are highly inductive. They don't like working at very high frequencies which can make them fail.

I suppose you mean Aluminum Electrolytic. The failure modes are not high frequency, but mainly heat (either because of the environment or because its ESR is relatively high, which means it's self heating). They also don't like reverse biases, the results of which can be very exciting. They're not "slower" because they're "inductive," they're "slower" because their values are typically much larger than ceramic types.

Tantalum: Medium/large and fast. They are less inductive than electrolytics. They can dump current far faster than electolytic which can cause undesirable current rushes.

Tantalums are also electrolytics. The electrolyte allows for larger capacitance in a given area. You REALLY don't want them to be reverse biased, and they have a bad tendency to explode if inrush current is too high. You don't want to use a tantalum as a DC block in audio circuits.

You also forgot some other capacitor types: polystyrene, mica, etc. These guys tend to be physically larger than a ceramic for a given capacitance, but they're a lot more stable. (And more expensive.) You'll find them in filter and integrator circuits, in high-frequency stuff, anywhere where stability is required.