Steve- Although it's not commonly touted as a "feature," ATX cases, MBs, and
power supplies were designed to be a lower cost configuration (for system
builders). One of the ways this was to be accomplished was to have the power
supply's fan drawing air from the outside of the case and blowing it *in*
over the CPU heat sink, thus allowing system builders to justify not using a
CPU fan. A true ATX power supply will have its fan on the lower (in a tower
case) surface of the P/S. It is a poor design (IMHO) to have no cooling fan
on the CPU, *especially* when there's no ATX-style P/S to provide a stream
of (relatively) cool air that blows over the CPU. When I first heard of this
design (in another list group), I thought it couldn't be true! Who would
draw air from the outside that would pick up heat from the P/S, and then
dump it on the CPU heat sink! I still believe it's a bad trade-off to save
$3-5 on a system build.

Strangely, I haven't seen very many "ATX" systems which have a full ATX P/S-
they seem typically to have a P/S w/ ATX power connectors, but the P/S fan
has the fan pulling air through the P/S and exhausting it at the back of the
system- the old way. And almost all still have the CPU fan mounted on the
heat sink. Sounds like your friend's system has the worst of both worlds!

Regards,
Jerry

----- Original Message -----
From: Steve Dias <[log in to unmask]>
To: <[log in to unmask]>
Sent: Thursday, August 26, 1999 9:54 AM
Subject: [PCBUILD] Celeron w/ no Fan (follow up)


> Hi All,
>     I posted a question about 3 weeks ago about this and just wanted to
let
> you know what I found. A friend's new Celeron PC reported no fan rpm in
the
> bios and a high operating temperature. When we finally got around to
opening
> the case we found that the socket 370 Celeron 400 is not equipped with a
cpu
> fan. It has just a large heatsink, about 2" thick, on it. There is also a
3"
> case exhaust fan near the cpu and the usual power supply fan, also blowing
> out of the case. The case fan is connected to a drive power lead, not the
> motherboard, therefore no fan rpm was being reported. He has an extended
> warranty on the PC, so we decided to just leave it as is and see what
> happens. I must admit, I haven't seen a PC without a cpu fan for a long
> time, guess it's just another cost cutting method.
>
> Steve
>
>          The PCBUILD web site always needs good submissions.  If
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