At 01:48 PM 8/11/97 +0930, you wrote:

>>No way - I know how they make these switch mode supplies and how the
>>transistors are treated prior to and during assembly - I wouldn't risk
>>the fire hazard. I've seen one go up and that was enough. I'd rather
>
>The power supply in mine has been running for about 3 years, more or less
>continuously.  Monitor is green, so it powers down and eliminates bulk of
>the kWh.  IMO, if it was going to fail, would have happened in first few
>months; a la bathtub curve.  All thats likely to happen now is a mains
>fault, and I've got some heavy iron taking care of that...  One good idea is
>to revers the fan and filter it, but make sure you clean the damn thing
>monthly or less.

No. What you seem to be operasting from is a sort of faith - best held in
terms of a dogma. I do not have such misplaced hope in the reliabilty of
electronics - we are realists aren't we ?

And you don't know when the other end of the bathtub curve will hit and
the bathtub curve is not 'L A W' it is only of statistical relevance and
bears little relationship to those random faults that can be traced back to
the way devices were treated during manufacture. Hewlett Packard did some
major report on this - anyone know where this is on the web ?

Would you want your house at risk because you hope your PC won't start
a fire because you have faith that it worked for 3 years 'therefore' it
won't fail catastrophically !?! Thats the sort of thinking that caused
the Shuttle debacle in which 7 people were killed - I might add it was a
heck of a bad management decision by nonengineering people.

Rgds (And yes I always wear seatbelts)

mike
perth, Western Australia