Igor Chudov wrote: > OK, thanks for saving my A$$ and giving me your first hand user > experience. I will look for something else. > > Which is kind of sad really. How hard is it to put together a fanless > system that consumes at most 20 watts and has a reliable power supply? > It may be very hard. As the semiconductor industry has moved to ever smaller dimensions on their chips, and ever thinner gate oxide, the reliability has gone down. The high current densities have made electromigration a problem that used to be entirely theoretical but now is a real failure mode after several power-on years. Hot electron trapping in the gate oxide has also caused degradation of logic level margins after a couple years. Industry pundits predict that the 45 nm chips may have a lifetime of about 3 years. Keeping them seriously cool should help, but this is a very worrisome progression.
I was showing my microVAX to the kids a couple days ago. The hard drive (or possibly controller) has croaked, but it still tried to boot. It ran continuously for 22 years as my main computer, and then running a legacy environmental monitoring application in and around my house. I retired it just in time, I hadn't got all the data off it before the drive quit. That kind of reliability was something I used to count on, and it is sad that the mainstream manufacturers no longer thinks that is important. CD players and cell phones are mostly powered off and just wake up every once in a while, so they avoid the early wearout. SuperMicro motherboards seem to be fairly reliable, the National Superconducting Cyclotron Lab at MSU (East Lansing) uses racks and racks of them. We have one of theirs at work, and the main bus bridge chip on it burned up, got a charred spot on it. It probably had 5 years running time on it by then, though. Jon ------------------------------------------------------------------------------ Nokia and AT&T present the 2010 Calling All Innovators-North America contest Create new apps & games for the Nokia N8 for consumers in U.S. and Canada $10 million total in prizes - $4M cash, 500 devices, nearly $6M in marketing Develop with Nokia Qt SDK, Web Runtime, or Java and Publish to Ovi Store http://p.sf.net/sfu/nokia-dev2dev _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
