P5K WS: CPU fan speed control and CPU temperature

I have installed a new P5K WS motherboard with a Sunbeam Core-Contact
Freezer cooler. The fan for the cooler is a bit loud (it runs at 2000
rpm); unable to see how to modulate the fan speed, I disconnected it
for a test. Running BurnIn for 60 minutes with the cooler with the
fan blowing through the tower, the idle temp raised from 29 degrees to
33-34C and held. Running without the fan, the temperature is about
44C. The MB temp stays about 39 degrees (temperatures are from PC
Probe II)

First of all, is 44 degrees terrible? I am running BurnIn for the
CPU (maths and SIMD [whatever that is]), memory, video 2D and 3D at
100 per cent) I am thinking that temps in the 65+ degree range are
not good.

Second, is there a way of controlling the speed of a CPU fan on this
model motherboard through the motherboard itself? If not, is there a
reliable 3rd party fan controller? (the control provided by
Sunbeamtech does not work when added between the board and the fan for
the cooling device)

Thanks
Ken K

ken k wrote:
I have installed a new P5K WS motherboard with a Sunbeam Core-Contact
Freezer cooler. The fan for the cooler is a bit loud (it runs at 2000
rpm); unable to see how to modulate the fan speed, I disconnected it
for a test. Running BurnIn for 60 minutes with the cooler with the
fan blowing through the tower, the idle temp raised from 29 degrees to
33-34C and held. Running without the fan, the temperature is about
44C. The MB temp stays about 39 degrees (temperatures are from PC
Probe II)

First of all, is 44 degrees terrible? I am running BurnIn for the
CPU (maths and SIMD [whatever that is]), memory, video 2D and 3D at
100 per cent) I am thinking that temps in the 65+ degree range are
not good.

Second, is there a way of controlling the speed of a CPU fan on this
model motherboard through the motherboard itself? If not, is there a
reliable 3rd party fan controller? (the control provided by
Sunbeamtech does not work when added between the board and the fan for
the cooling device)

Thanks
Ken K

Generally, we're only interested in the peak temperature, under load.
Under no load, the CPU will run at some more reasonable temp.

So, run Prime95 with a thread per core, and see how hot it gets. As you
say, a CPU temperature of under 65C under load, is desirable. If you go
too much higher, the Intel processor will start to "throttle". A program
like RMClock can be used to detect throttling.

http://www.mersenne.org/gimps/p95v256.zip

You can see RMClock detecting throttling, here.

http://www.xbitlabs.com/articles/cpu...c-guide_7.html

The fan controller on the Sunbeam, is shown as a three pinner. You should
have been able to plug that into a four pin CPU fan header (leaving the
PWM pin unconnected), and then the adjustment knob should have worked.
You could test, using a three pin motherboard header, and plug in one
of your case fans to it.

The motherboard usually wants to see pulses on the CPU fan header and its
RPM signal. The BIOS may shut the board off, if it thinks the fan has failed,
or there is no fan present. You could, if you wanted, plug the Sunbeam
fan controller, into another (three pin) fan header, but you'd want to
plug some other monitored fan into the CPU header. So whatever you
decide to do, there should be a fan with a working RPM signal, plugged
into the CPU header.

They list a ridiculously low theta_R for this cooler, so I hope it
actually achieves those numbers in practice.

http://www.sunbeamtech.com/PRODUCTS/...ctFreezer.html

For example, say you had a 100 watt TDP processor. The theta_R is
listed as 0.092C/W . Say the room temp is 25C, and the computer
case air temperature is 35C (a relatively well cooled computer case).
Then the CPU temp would be 35C + (100W * 0.092C/@) = 44.2C .
That can only happen, if the flatness of the two surfaces
is such, that the heatpipes are making good contact. I
remember seeing a review for some other product, that uses
the "raw heat pipe" contact technique, and it actually sucked
at it. So load up Prime95, and do the math for whatever processor
TDP you've got, and see if the thermal performance matches.
Based on the math, you should have no trouble meeting 65C,
and should be able to turn the fan down.

I make my own, home made fan controllers. I get a pack of
1N4000 series diodes, at a local electronics store. They cost
about $0.10 each. Each diode drops about 0.7V when forward
biased. I put six or seven diodes in a row, and connect to
+12V, to get a reduced voltage for a fan. The tough part,
is packaging the solution. A little piece of perfboard would
likely do a better job, than what I put together :-) I like
the ghetto solutions. And no, it isn't adjustable (except
by adding or removing diodes). I suppose I could put a
very expensive wafer switch, to make them selectable,
but then the price would be well outside the $0.70 total
so far.

Zalman makes the FanMate2 adjuster, but I believe it has
a 6W limit (12V @ 0.5A). The Sunbeam current is under
that value, so it would probably work. But I'd rather see
more choices than that in the industry. Using a bulky
tray mount solution (three channel) for this application,
is overkill.

Paul