On Tue, 16 Sep 2003 02:28:12 GMT, "Mitchua" wrote:

I know what you mean. I'm trying to escape a 1800+ right now on an Asus
board that runs pretty hot (at least 49Celcius). A friend told me that the
P4's run a lot cooler, and hence, don't need the huge noisy heatsinks/fans.
Actually, I saw a P4 running with an undervolted stock heatsink/fan quite
comfortably. However, checking out temperature readings online, they still
seem to run above 40Celcius. That's why I thought for the extra $100 that a
P4 would cost me, I might as well buy a nice case and a Zalman 7000CU quiet
heatsink or something. Make sense?

A P4 may idle at lower temp but a properly designed system will have
enough cooling for the CPU's full-load state. Through careful
selection of thermally-controlled fans the P4 system can be quiter at
low-load, but if the system is hardly ever running near full-load, the
better solution might be a slower CPU (even within same family of CPU)
and reducing the CPU core voltage if possible. Manufacturers spec the
default cpu voltage to cover a range of speeds and yields to make
implentation easier for motherbaord manufacturers, but the particular
specimen of CPU dictates the actual voltage needed to retain stability
at a given frequency of operation. Given the willness to test the
stability and a motherboard with CPU core voltage options (or modding
the CPU and/or board to accomplish same end result), heat ouput can be
reduced by only using enough voltage to keep the CPU stable, but of
course the closer you come to the bare minimum voltage, the more
extensive (and lengthly) the stability testing process must be.

When considering prices, first budget for a well-designed case and
optimal 3rd party fans for that case, or have a willingness to mod a
less-optimal case. Then budget for a good aftermarket heatsink (and
3rd party fan if 'sink doesn't come with EXACTLY what you want).
These items make the most difference, would allow use of either (P4 or
Athlon) without cooling issues, at relatively low-to-quiet noise
levels except in the most extreme of conditions. Always provide
adequate case & heatsink for the system to be running 24/7 at full
load. If they system hardly ever runs at full load then careful
selection of thermally-throttled fans (or add-on fan controller) might
be worthwhile, and/or reduce CPU speed and core voltage as
forementioned.

49C isn't all that hot for a CPU, they are designed to operate fine at
this temp given a stable motherboard (power). More significant might
be the other components subject to lifespan reduction at higher temps,
like hard drives, motherboard power regulation circuits (capacitors).



Dave