Do you have an Asus motherboard and an Athlon64?

meglamaniac · Post by **meglamaniac** » Wed Jan 05, 2005 1:15 am

Not sure if this should be here or in the Fans forum, it's a bit half and half.
I am looking to get an Asus A8N-E Premium board when they become available (Feb now, apparently. Grr.) so I was looking for information to do with how Asus's Q-fan system works in combination with AMD's Cool'n'Quiet.
Here is what I found on another forum, and it seems quite interesting.

To expand/clarify.....

If you have enabled both Cool n' Quiet and Q-Fan than yes the CPU fan will go OFF after a boot--- if the demand on your CPU is nominal and will not start spinning again until either the CPU demand goes up and/or the threshold temp controlled by the Q-Fan kicks the fan "virtual" start button.

If you have just Cool n' Quiet enabled but Q-Fan OFF than the CPU Fan will run continuously and the speed will increase/decrease based upon the CPU demand.

If you have Cool n' Quiet OFF but Q-Fan ON then the CPU fan will go OFF after a boot depending upon again the CPU demand and will be triggered back on when the threshold temp of Q-Fan is reached.

Obviously I'm particularly interested by the prospect of the first mode of operation (both enabled) where the CPU fan will actually stop. This seems an ideal solution to me.

Does anyone here have a combination of an Asus board and an Athlon64 processor, and if so how accurate is this information?

Thanks.

luggage · Post by **luggage** » Wed Jan 05, 2005 2:36 am

That is how my rig works. See sig.

Now mine has the old via chipset and a rather cool 2800+ so I cant tell you for sure about your particular board, cpu and case...

If you have just Cool n' Quiet enabled but Q-Fan OFF than the CPU Fan will run continuously and the speed will increase/decrease based upon the CPU demand.

This is probably only true with the thermally controlled default HSF or any other thermally controlled HSF.

meglamaniac · Post by **meglamaniac** » Wed Jan 05, 2005 3:36 am

luggage wrote:This is probably only true with the thermally controlled default HSF or any other thermally controlled HSF.

Yeah, that sounds about right.
On page 8 of AMD's official documentation (PDF) it states:

4. Required for noise reduction: Heatsink/fan capable of speed control All AMD Athlon 64 Processor-In-A-Box packages include thermally controlled fans. A thermally controlled fan detects the current temperature of the processor using a thermistor, and when a lower temperature is detected the fan speed and noise is then reduced. Upon detection of a higher temperature the fan speed is resumed at full speed to appropriately cool the processor. If an AMD Athlon 64 Processor-In-A-Box package is not used, an appropriate 3rd party heatsink with a thermally controlled fan must be used.

In your case (and in mine, hopefully) the combination of a standard fan and Asus's Q-fan results in a thermistor controlled fan and the result is the same: the fan stops at low load.
The advantage of Q-fan over a "real" thermistor fan is, of course, that we can fiddle with the threshold settings to suit our own needs

Nightwatch · Post by **Nightwatch** » Wed Jan 05, 2005 8:34 am

Yup, I have an asus K8V motherboard with an A64 3200 Processor-In-A-Box, and the fan stops when the thermal load isn't too high. ( Both Cool n' Quiet and Q-Fan enabled)