INTEL COOLING SYSTEM

Hello, I have a P 4 3.2 E (prescott) with air cooling by a Intel C91249
Socket-478 Copper Core Cooling Fan, P/N: C91249-002 / C91249-003. Now, the
fan is supposed to run variable, slow in low temps. and fast in high temps.
The problem is that in 37ºC of cpu temperatura, the fan runs at 2500 rpm
(max.). It should run slower! This is verifyed in BIOS. Are there any
configuration missing? Will the instalation of the chipset of the mainboard
help?

System
Windows Vista 32
Asrock P4i65G
1G DDR~
The CPU fan is connected to the mainboard

Thanks in advance
Manuel

MS wrote:
Hello, I have a P 4 3.2 E (prescott) with air cooling by a Intel C91249
Socket-478 Copper Core Cooling Fan, P/N: C91249-002 / C91249-003. Now,
the fan is supposed to run variable, slow in low temps. and fast in high
temps. The problem is that in 37ºC of cpu temperatura, the fan runs at
2500 rpm (max.). It should run slower! This is verifyed in BIOS. Are
there any configuration missing? Will the instalation of the chipset of
the mainboard help?

System
Windows Vista 32
Asrock P4i65G
1G DDR~
The CPU fan is connected to the mainboard

Thanks in advance
Manuel

The Intel fan may have a thermistor inside the
hub of the fan. It senses the computer case
air temperature (not the CPU temperature itself).
The thermistor gives the fan a temperature sensitive
speed characteristic. The reason Intel set it up
that way, is to make the fan compensate for a hot
room. If the room gets hot, Intel makes the fan
work harder, in order to keep the CPU cool.
Since the fan itself is not in contact with the CPU,
they cannot make the fan directly measure the CPU
temperature. So they sensed the case air temperature
instead.

If you take the side off your computer case, you
may notice the Intel fan slows down. That would be
because you've let the warm air out of the computer
case. If that happens, it means there is not
sufficient airflow through the computer case, to
keep the case air temperature down. So the CPU
fan screams in protest, that the case cooling is
not sufficient.

To fix that, you'd either put a better exhaust
fan on the back of the computer case, or expand
the intake vent area, so that there is less
resistance to airflow. (I had to open up vent
area on the front of my Antec Sonata, to get
better cooling.)

In addition to the Intel thermistor, the motherboard
may also exert some control. Some motherboards have
the ability to vary the voltage fed to the fan. So
that can be used to make the fan run slower as well.
Not many motherboards include control of all the fans.
Only a few Dell/HP type machines have all fan headers
with voltage control. My current Asrock board, that
I'm typing this message on, has no voltage control
options for any fan header.

My suspicion is your case air is too hot. If the
room temperature is 25C, a well cooled computer
case internal air temperature, would be 32C (a
7C rise).

Paul

"MS" wrote in message
...
Hello, I have a P 4 3.2 E (prescott) with air cooling by a Intel C91249
Socket-478 Copper Core Cooling Fan, P/N: C91249-002 / C91249-003. Now, the
fan is supposed to run variable, slow in low temps. and fast in high
temps. The problem is that in 37ºC of cpu temperatura, the fan runs at
2500 rpm (max.). It should run slower! This is verifyed in BIOS. Are there
any configuration missing? Will the instalation of the chipset of the
mainboard help?

System
Windows Vista 32
Asrock P4i65G
1G DDR~
The CPU fan is connected to the mainboard

Thanks in advance
Manuel

A couple of questions.

- Does your motherboard have CPU fan control capability in
the BIOS? Asus boards have Q-Fan, but I don't know if their
Asrock series boards have this.

- Do you have it enabled?

If your board doesn't have CPU fan control, then as Paul
suggested, it's relying on the fan's built in temperature
sensing speed control. I have found that Intel CPU fans
with built-in temperature sensing have not shown much
variation in speed. It's that 2500 RPM that's keeping
your CPU at 37C. At 2000 RPM, I can guarantee your
P4 will be in the 40s.

Wel the Asrock doesnot have any fan regulation at all. It's a low buget
model. There is no need for 2500 rpm at 37ºC...

"Ian D" escreveu na mensagem
...

"MS" wrote in message
...
Hello, I have a P 4 3.2 E (prescott) with air cooling by a Intel C91249
Socket-478 Copper Core Cooling Fan, P/N: C91249-002 / C91249-003. Now,
the fan is supposed to run variable, slow in low temps. and fast in high
temps. The problem is that in 37ºC of cpu temperatura, the fan runs at
2500 rpm (max.). It should run slower! This is verifyed in BIOS. Are
there any configuration missing? Will the instalation of the chipset of
the mainboard help?

System
Windows Vista 32
Asrock P4i65G
1G DDR~
The CPU fan is connected to the mainboard

Thanks in advance
Manuel

A couple of questions.

- Does your motherboard have CPU fan control capability in
the BIOS? Asus boards have Q-Fan, but I don't know if their
Asrock series boards have this.

- Do you have it enabled?

If your board doesn't have CPU fan control, then as Paul
suggested, it's relying on the fan's built in temperature
sensing speed control. I have found that Intel CPU fans
with built-in temperature sensing have not shown much
variation in speed. It's that 2500 RPM that's keeping
your CPU at 37C. At 2000 RPM, I can guarantee your
P4 will be in the 40s.

MS wrote:
Wel the Asrock doesnot have any fan regulation at all. It's a low buget
model. There is no need for 2500 rpm at 37ºC...


Does the Intel fan run slower, when you take the side cover off the
computer case ?

Paul

"MS" wrote in message
...
Wel the Asrock doesnot have any fan regulation at all. It's a low buget
model. There is no need for 2500 rpm at 37ºC...


You could get a fan speed controller, such as the Zalman Fanmate,
if you're not satisfied with that speed. If you slow the fan to
about 2000 RPM, your CPU temp will probably be in the low to
mid 40s C. Just make sure your CPU doesn't get too hot under
maximum load with your selected speed.

The fanmates are nice. I used one in my second build and most of the time,
I could turn the fan speed all the way down.

This made for a quiet pc.

--g