Hi,

> It seems reasonable that the power supply that this customer is using is
> occasionally doing something that our board finds disagreeable, but what?
> And why only when first assembled and never in the field? It would be
> extremely helpful if we had some idea what to ask this customer to
> investigate...

    The power supply is a suspect but it is hard to imagine a glitch that
causes problems on any of the 3 supply line that you are using and usually
it would cause problems with the motherboard also !

    I would look for possible ESD induced failures, either in manufacturing,
transportation or at the client installation procedure. It would cause CMOS
latchtup and then burn the chip to death.. To me this seems to be the most
probable cause of failure.

Best regards,
Alexandre Guimaraes

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