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larry moe 'n curly larry moe 'n curly is offline
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Default Power surges and modern electronics.



Chuck wrote:

On Mon, 13 Dec 2010 18:02:46 -0800 (PST), "larry moe 'n curly"
wrote:

Jeff Liebermann wrote:

On Fri, 10 Dec 2010 12:11:00 -0800 (PST), Bob Villa
wrote:

Third, most flat panel sets are put together out of crappy components,
especially the capacitors.

Dell is hoping there are no more of those crappy-caps around!

Dell was not using "crappy" capacitors. What they were doing is the
same thing that almost every other manufactory is currently also
doing. They are rating their electrolytics as close to the bitter
edge of failure as possible. That saves a few pennies in cost by
using a lower voltage electrolytic but shortens the capacitor life. My
guess(tm) is that Dell's OEM supplier in China selected the capacitors
based upon faulty calculations, where it was designed to blow up in
about 5 years, instead of the 1-2 years specified in the class action
suit.


I don't know about Dell LCDs, but their computer motherboards of 5-8
years ago that failed at high rates were actually made with very good
brands of capacitors, like Rubycon, Nichicon, and Panasonic, not the
common crap found on many other motherboards . Unfortunately Nichicon
produced bad batches of their HM and HN series caps, marked HM(M) and
HN(M), from around 2001-2004.


Just finished working on a Dell Optiplex that has 8 Rubyicon 1800 uf
6,3v caps in a row; all of which were leaking out the top of the caps.
The failure rate of Rubycon capacitors was high back when I was
repairing televisions, particularly Mitsubishis of the late 90s.
Chuck


The Pentium4 CPUs in those Dells were such power hogs that even
Rubycons would usually wear out in about 5 years.

Why has my 1976 Sanyo TV needed only 2 caps replaced (audio coupling,
vertical yoke)? The 2-year-old digital converter box that sits on top
of it has needed a lot more caps replaced.