PC form factor - test-drb@ccmp.vtda.org

1 Jul 1999

That's quite correct.  It was a stupid, Stupid, STUPID plan exhausting air
...
 from the PC and drawing air through all the
front-loading devices, e.g disk drives, etc.  That prevented a nice sensible
filtering scheme like many
people have implemented by adding a fan to the PSU after reversing the fan
that's in there.  They sandwich a filter between the fans to offset the head
loss due to the filter.  This keeps the power supply components much
cleaner, as well as keeping the dust from settling so quickly on internal
components.  The cooling is substantially improved and the dust accumulation
is decimated.  All this extends the life of not only the power supply, but
the active components in the PC as well, as the heat transfer is more
efficient when laminar flow at the component surfaces isn't hampered by dust
most of the time.

Dick

-----Original Message-----
From: Allison J Parent &lt;allisonp(a)world.std.com&gt;
To: Discussion re-collecting of classic computers
&lt;classiccmp(a)u.washington.edu&gt;
Date: Thursday, July 01, 1999 8:52 PM
Subject: Re: PC form factor

...
 <I'm wondering: was the IBM PC the first machine
with PSU in the rear
<right, drives in the front right, motherboard in rear left, or did they
<borrow this design from someone else?

I don't think it was borrowed as much as there are few choices when
you put most of the meat on one card.  Packaging hardware is an
older art than the PC.

Personally it was a horrid layout with poor airflow for cooling.

Allison