->> FWIW: proper ATX power supplies pull fresh air thru
->> the power supply and blow it directly across the CPU
->> assembly... exit ports in the case vary from there...
->> true ATX power supply fans are not accessible from
->> the back of the case, either...

 TW>  Cannot say I have seen one that works that way. But
 TW> then I am not well aquanted with Mutipule Fan Power
 TW> Supplies

nothing was said about multiple fans in the power supply ;)

this information is available in the ATX specifications... i just googled
for "ATX Specification" sans quotes and one of the top hits was
this...

====== snip ======

Modified Fan Direction and Placement: One of the goals of the original ATX
specification was to change the way the power supply fan  worked. At around
the time ATX was introduced, cooling fans were becoming the standard for
the newer, faster CPUs on the market. Instead of exhausting air out the
back of the case as had always been the norm, Intel wanted to use this
exhaust air to cool the processor directly, saving the cost of a cooling
fan. Therefore, the ATX specification calls for the fan to run in the
opposite direction and be placed near the CPU's location on the
motherboard, to blow on it for cooling. The other advantage of this method
is that it keeps the system cleaner, since air entering the case all comes
from one place, and can be filtered if necessary.

Unfortunately, while a good idea, this hasn't worked out quite the way
Intel hoped. The primary problem is that newer CPUs continue to generate
more and more heat as they get faster, and a regular power supply fan
doesn't have enough flow to cool them properly. This problem is compounded
by the fact that the air blowing on the CPU is warmed by the components in
the power supply itself, so it is several degrees above ambient temperature
before it ever gets near the CPU. Thus, newer versions of the ATX
specification make the fan direction optional. The newest ATX power
supplies have gone back to the old style of placing the fan on the back of
the power supply and exhausting air to the outside.

====== snip ======

 TW> staying a bit behind the Curve. I have other priorities
 TW> like Housinf and Eating to satisfy FIRST!! BUT I have
 TW> seen systems where the CPU has a duct form the CPU to
 TW> the bottom of the PS and the PS Sucks the Heat Away form
 TW> the CPU and it exits out of the PS at the back of the
 TW> machine..

i kinda like the refridgerated and water-cooled systems, myself ;)

)\/(ark