Hi mark!

 ml> FWIW: proper ATX power supplies pull fresh air thru the power supply 
 ml> and blow it directly across the CPU assembly... exit ports in the 
 ml> case vary from there... true ATX power supply fans are not accessible 
 ml> from the back of the case, either...
I think the ATX 2.0 standard allows both. I think people realized that
blowing hot air from inside the power supply over the CPU didn't really
help cooling. Back when ATX power supplies were first "invented",
the air flow from the power supply plus a passive cooler were enough for
most CPUs, but nowadays this doesn't work for much of them.

 ml> unfortunately, many ATX power supplies are simply reworked AT power 
 ml> supplies and do continue to do things the old way...
That, too.

Ciao
Pascal

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