Fan Stops if Speed reduced < 95 %

[saroneo]

Hi,

When I run speedfan and reduce the speed of either system fan or cpu fan below 95%, the fan completely stops !!

If I enable the "SMART" fan feature in the BIOS, to automatically decrease the speed of my fan when the temp is normal, the fan completely stops.

I am using a Biostar P4TSV MicorATX motherboard. Looks like the BIOS is reducing the voltage to reduce the speed, but I guess it is too low for my Fan to spin ?

Do I have to get some special fan to make
it spin at lower RPMs ?

I use a Antec FAN for the Sytem FAn and the stock Intel FAn for CPU.

Please advice.

thanks,
Saroneo

[DallasDon]

The short answer is Yes.

Some fans are designed as variable speed, some can be wired with a combination of the -5V rail and the +12 V rail, to yeild 7 volts, and run at about 3/4 speed.

You will find some led fans will run with reduced speeds, but the led lights will flicker or go out below 7 volts.

The best solution is a CPU fan designed for varibale speeds, and possible experiment with a fan controller for your case fans.

Some power supplies even have temp controlled varialble fan speed.