Yea those computer desk that have 1 small cable hole in the bottom and a door, that hides the machine in a hotbox so speak. THose are aweful I’ve seen new systems just idling, but the fan is running wide open 5000 rpm’s and it sounds likela vacuum and the customer wonders why it so loud and complains. Then you open the door for 1 minute and the fan drops to a whisper at 1800 rpm’s, they see this and go: Oh.
The root cause of the failing capacitors is industrial espionage gone wrong. Several Taiwanese electrolyte manufacturers began using a stolen formula that was incomplete, and lacked ingredients needed to produce a stable capacitor.
Published: November 10, 2005, 4:00 AM PST
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At issue are faulty capacitors on motherboards that store power and regulate voltage. Defective capacitors found in the Dell Optiplex workstations, some Apple iMac G5s, HP xw-series workstations made in 2004 and PCs with the Intel D865GBF motherboard have been found to bulge, pop, leak and crust over, causing video failure and periodic system shutdowns.
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Only HP would identify the maker of its faulty capacitors: Nichicon, of Kyoto, Japan.
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Various postings on message boards claim the trouble was caused by capacitors that were overfilled with a liquid electrolyte that helps the component protect the processor from excess power; convert energy from 5 volts to around 1.5 volts; and deal with current surges. The PC makers have not confirmed that that was the problem.
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This is hardly the first time a bad capacitor problem has popped up. Three years ago, in what appears to an entirely different situation, an industry-wide problem was reported by Passive Component magazine. The publication unearthed a problem with capacitors made by several Taiwanese manufacturing companies.
Caps should only be run at a certain percentage of their maximum capacity. Engineering the board to run them above (??50-80%??) can cause premature failure. Awhile back I read a very good explaination on this somewhere and I believe they also stated that they’re susceptible to premature failure when exposed to frequencies that they weren’t designed to handle.
They sometimes do a very good job with layman’s explainations. Sometimes they miss important details in their explaination of things… over-simplification I guess. Reading their artucles however will always help you to refine your search terms in Googling more specific details.
It’s the age old thing really, things are made to sell at a particular price point - in short quality suffers. I can buy all sorts of makes and models of capacitors from one of my suppliers, yet non of those components are inferior and subsequently they no doubt cost far more than what motherboard manufacturers pay and that’s not just to do with massive bulk buying either. Usually capacitors rated at 85C (centigrade) are cheaper than those rated at 105C - there are so many things that can be stripped from the specifications so as to make the price far cheaper.
Also things like Molex and AMP pins for their ranges of plugs and sockets, gold plated ones can cost up to 3 times the amount of the standard tinned type pins.
Gigabyte has a new motherboard technology, part of which is the better, solid capacitors used....6 times the lifetime....
I remember back in the late 1960’s when Tantalum electrolytic capacitors came on the market and began replacing the older electrolytic capacitors. They were many times smaller for the same microfarad and voltage rating, but we experienced a higher failure rate. Tantalums have improved since, but now with the introduction of the more reliable solid Tantalum capacitors, you’d think they couldn’t do any better, but now there’re making solid polymer aluminum capacitors touting even higher reliability at high temperatures.
http://powerelectronics.com/mag/power_new_solid_polymer/index.html
Gigabyte has a new motherboard technology, part of which is the better, solid capacitors used....6 times the lifetime....
I remember back in the late 1960’s when Tantalum electrolytic capacitors came on the market and began replacing the older electrolytic capacitors. They were many times smaller for the same microfarad and voltage rating, but we experienced a higher failure rate. Tantalums have improved since, but now with the introduction of the more reliable solid Tantalum capacitors, you’d think they couldn’t do any better, but now there’re making solid polymer aluminum capacitors touting even higher reliability at high temperatures.
http://powerelectronics.com/mag/power_new_solid_polymer/index.html
Wow! What next?
Tantalum’s did have such a bad reputation. I would be working on the bench with a can of freezer in one hand and a hair dryer in the other! They have improved as you say and still have advantages such as low ESR.
Technology always seems to be improving, equally though ways to cut corners for the mass budget Chinese markets seems to be rife too.
