From: "Phil Seakins" <pseakins@AKAMAIL.COM>
> >>>Floppy drives are used so little these days, and as the fan in the
power
> >>>supply sucks instead of blows (thanks to IBM) the floppy drive spends
day
> >>>after day collecting dust. When you finally come to use it, it is
filthy.
> >>>In days of yore, regular usage helped keep the heads relatively dust
free.
> >>These are both very good points, Sean. One notices the cabinet full of
dust,
> >>if opened after a couple of weeks. In which case, might it help if you
just
> >>reverse the facing of the fan in the SMPS? Maybe not a solution to the
drive
> >>problem, but would perhaps keep your cabinet a lot cleaner?
> >This was Phil's comment actually, Anand, and personally I don't agree
with
> >it. Whether the fan "sucks" or "blows" is irrelevant. It doesn't matter
if
> >the fan "sucks" or "blows" from or into the casing. The air has to enter
> >and discharge from the case for there to be an airflow. If there is a
flow
> >of air, then the dust will be brought into the case no matter what. The
> >only remedy is to filter the air at the point(s) where air is entering
the
> >casing.
> Precisely, and if indeed the fan sucked instead of blowing then all you
> would need would be a filter on the power supply fan inlet port. Instead,
> air and dust is drawn in unfiltered through every little nook and cranny
in
> your PC casing including the floppy drive opening. But, because IBM put
the
> fan in backwards when they released the first PC in the 80's, every clone
> vendor ever since has copied this error.

Well, this wasn't an error like you say.
It has to do with power and heat.  A high load PSU today would be about 70%
effective in regulating the power to the computer... (look it up someone?)
This would mean that if the power drew about 200watts, dissapated about 60w
and delivered about 140w.  60w would be a lot of hot air if sucked into the
computer.  Blown out instead would mean a 30% reduction in total heat
dissapated in case.  30% is a lot in such circumstances...

They were a lot poorer before.

    KreAture

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