Best quality motherboards for AMD
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From: Ken on 27 Mar 2010 05:47 I had some capacitor problems too. Less than 2 years in use. I replaced them year 2009. http://tekniken.se/docs/image/example/itx_cap_ce11.jpg http://tekniken.se/docs/image/example/m2-atx_cap_c28.jpg http://tekniken.se/docs/image/example/m2-atx_cap_c47.jpg http://tekniken.se/docs/image/example/m2-atx_cap_c48.jpg
From: larry moe 'n curly on 27 Mar 2010 10:12 RayLopez99 wrote: > On Mar 25, 10:38 pm, Daniel Prince <neutri...(a)ca.rr.com> wrote: > > > Are Gigabyte and ASUS the only companies that make motherboards for > > AMD with all solid polymer capacitors? How do they compare in terms > > of quality, longevity and customer support? > > Why the fixation with these capacitors? With most consumers it's just because "solid polymer" is trendy, but those caps have been more reliable than the average wet ones, probably because the vast majority of polymer caps are made mostly by quality manufacturers, that is, Japanese companies, or maybe it's just not possible to goof up the solid material the way electrolyte can be.
From: Daniel Prince on 1 Apr 2010 08:16 "larry moe 'n curly" <larrymoencurly(a)my-deja.com> wrote: >OTOH high quality wet electrolytic caps can easily last 10 >years, How cool do they have to be keep to last 10 years? -- I don't understand why they make gourmet cat foods. I have known many cats in my life and none of them were gourmets. They were all gourmands!
From: Paul on 1 Apr 2010 14:39 Daniel Prince wrote: > "larry moe 'n curly" <larrymoencurly(a)my-deja.com> wrote: > >> OTOH high quality wet electrolytic caps can easily last 10 >> years, > > How cool do they have to be keep to last 10 years? The capacitor thing, uses a modified Arrhenius relationship. In chemistry, Arrhenius predicts that chemistry reaction rate, doubles for every 7C rise in temperature. For capacitors, they do a curve fit, and the exponent isn't quite the same as the one in chemistry. Capacitor reliability may double, for anywhere from 10C temperature rise, to 15C temperature rise. http://www.rubycon.co.jp/en/catalog/e_pdfs/aluminum/e_MBZ_MCZ.pdf The data sheet has the basic endurance stated in it. In small print... 2000hrs at 105�C, Say the temperature inside the computer case is 35C. From 105 down to 35, gives us 70C to work with. (I'm ignoring core heating in the cap, for simplicity.) Just picking a number, if the lifetime doubles for every 10C, that is 7 doublings or 2**7 times longer life, or 2000 * 2**7 = 256000 hours or 29 years of operation. If you pick a different number, like 15C for the modified Arrhenius factor, you might be looking at 2000 * 2**5 = 64000 hours or 7.3 years of continuous usage. Each manufacturer will provide a web page or data somewhere, as to the modified Arrhenius factor. (They do curve fitting to measured data, to get it. You cannot assume every manufacturer gets the same answer. Some of them will cheat and use the measurements of others.) They mention 10C in this note, plus 15 year service life independent of the Arrhenius calculation. The 15 year service life is based on the rubber bung in the bottom of the cap, drying out and failing to maintain the seal on the capacitor. Rubber is attacked by things like ozone, and local conditions might cause the rubber to fail before that estimate. (Consider how long a rubber band lasts in your environment, to get some idea of what is happening to rubber.) If your Arrhenius calculation comes out to 29 years, then the 15 year service life overrides that calculation. And the service life isn't a "guaranteed fail", it would represent some percentage of the caps in service, needing to be replaced. http://www.rubycon.co.jp/en/products/alumi/pdf/Life.pdf When electronic equipment is designed, "Service Life" is a factor which is stated in the high level architecture documents. Where I worked, at one time, that number might have been 20 years, while later the number dropped to 10 years. A change in the Service Life for a line of products, gives the engineer more room for cost cutting. To meet 20 years, might take extensive component testing, usage of more expensive components, or a complete change in implementation (say a digital VRM with Volterra, rather than the usual Vcore implementation). I have no idea what the "Service Life" target for motherboards is. Presumably, it is longer than the 3 year warranty :-) But not by much. If you can find similar documents for solid polymer caps, you could go through a similar analysis, to see what they're buying you. Paul
From: Daniel Prince on 1 Apr 2010 22:40
Paul <nospam(a)needed.com> wrote: >Daniel Prince wrote: >> "larry moe 'n curly" <larrymoencurly(a)my-deja.com> wrote: >> >>> OTOH high quality wet electrolytic caps can easily last 10 >>> years, >> >> How cool do they have to be keep to last 10 years? > >The capacitor thing, uses a modified Arrhenius relationship. In >chemistry, Arrhenius predicts that chemistry reaction rate, doubles >for every 7C rise in temperature. For capacitors, they do a curve >fit, and the exponent isn't quite the same as the one in chemistry. >Capacitor reliability may double, for anywhere from 10C temperature >rise, to 15C temperature rise. I think you mean "half" not double or you mean "temperature decrease" not "rise". > >http://www.rubycon.co.jp/en/catalog/e_pdfs/aluminum/e_MBZ_MCZ.pdf > >The data sheet has the basic endurance stated in it. In small print... > > 2000hrs at 105�C, > >Say the temperature inside the computer case is 35C. From 105 down >to 35, gives us 70C to work with. (I'm ignoring core heating in >the cap, for simplicity.) > >Just picking a number, if the lifetime doubles for every 10C, that >is 7 doublings or 2**7 times longer life, or 2000 * 2**7 = 256000 hours >or 29 years of operation. > >If you can find similar documents for solid polymer caps, you could >go through a similar analysis, to see what they're buying you. I think you mean "selling you". ASUS claims that their solid polymer caps will last 57 years at 60 degrees C (140 F). I think 60 C is warmer than any decent case will get. -- I don't understand why they make gourmet cat foods. I have known many cats in my life and none of them were gourmets. They were all gourmands! |