Capacitors

Load Life

Measured in hours, this is an indication of the estimated number of hours a capacitor will operate before it is expected to fail. The failure rate of capacitors follows a bathtub-like curve against the working temperature. Most manufacturers rate their capacitor's load life at its highest-rated ambient temperature, which is usually 50-55 °C. So, don't be surprised to see a capacitor load life of only 2000 hours.

The actual lifespan of a capacitor is proportionate to the ambient temperature. Here's a simple formula I created for the purpose of simplifying capacitor lifespan from a bunch of different numbers.

RT = Rated Temperature in Celsius
OT = Operating Temperature in Celsius
RL = Real Lifespan in hours
E23 = Empire23 (just a placeholder symbol!)

Start by using this formula to derive a number which is symbolized by E23.

(RT – OT) / 10 = E23

Then use E23 in this formula :

Real Lifespan, RL = RT x 2^E23

Solid Or Liquid?

Solid capacitors are the rage these days but I'm sure some of you will be wondering if it's for real... or if it's just marketing fluff. Well, solid capacitors are really the real deal. Taking the liquid electrolyte out of capacitor improves both its performance as well as its reliability. Solid capacitors usually have better ripple ratings and superior ESR; and the best part is, without the liquid electrolyte, there's no risk of anything turning into gas and blowing up. That's why polymer capacitors have no need for vents on their tops.

In short, the performance and reliability of solid capacitors is significantly greater than that of traditional liquid electrolyte capacitors. So if you can afford it, get a motherboard built with solid capacitors, but do not ignore the other factors that make a good, reliable motherboard. You can make a good motherboard without solid capacitors, but they cannot make a lousy motherboard better just by using solid capacitors.

Before I forget, most solid capacitors are much smaller than their liquid counterparts. So, they generally do not have their brand names printed on them, only their series codes. So, looking around for their datasheets might be harder.

Brand Factor

Let's face it, some capacitor manufacturers are known to cheat, resort to flim-flam fakery, bloated numbers and dubious testing methods. Their position in the market is also flimsy at best, making their track records even more untrustworthy. So my advice is to stick to the better brands. Brands you should look out for are Sanyo, Rubycon, Nippon Chemicon, Matsushita, Nichicon, Elna and Samxon.

As you can see, most of these companies are Japanese. Don't know why but they seem to make great capacitors. Samxon is Taiwanese/Chinese but they have an impressive track record and great products. If you do need more in-depth information on capacitors and their production, here's a good link from the nice folks at Rubycon : http://nichicon-us.com/english/lib/aluminum.pdf.

Capacitor-less Motherboards

Frankly speaking, that's total bullshit. It not that these motherboards do not have capacitors, it's just that they replaced the original can-type electrolytic capacitors with polymer SMD or ceramic capacitors are small and do not look like the regular can-type capacitors. They have extremely low ESRs and very high ripple tolerance, but lack bulk capacitance. Either way, they're still subject to the metrics we covered earlier.

For now, I rather not buy into them until I get more solid information on them. In theory though, they should function perfectly as well as, if not better than electrolytic capacitors, in most cases. Okay, enough with capacitors, let's talk about power delivery!