At 08:05 PM 3/11/2003 -0500, you wrote:
>I think the rationale for the original ATX design, with the P/S fan blowing
>in was to have it blowing across the CPU heatsink.  (Or, am I being too kind
>to whoever came up with that idea?)

The idea behind the original ATX power supply, which appeared with the
Pentium II Slot One chip, and which had the power supply fan blowing cool
air in, positioned over the CPU and card slots, was to use the fan for
multi purposes, and more importantly pressurize the case.

If you have the air blowing in, and nothing going out, then a higher
pressure is created inside in the case, and dust and dirt is kept out by
air pressure, rather then being forced, in by the cooling fans. Sounds nice
in theory, but hasn't t worked out too well in practice, for modern
processors,that run hot.

Even in it's time,  power users immediately started reversing the PS fan,
and adding additional fans, to bring cool air into the case, and suck hot
air out.

Rode
The NOSPIN Group
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