CPU fan speed running at 100%

[generaltso]

I had a GIGABYTE GA-EP35-DS3L running with a E6550 for about a year before the motherboard took a dump on me. I am going to RMA it, but in the mean time I am running a GIGABYTE GA-G31M-S2L. Everything is fine, but one problem. On the new board (the G31M), the CPU fan is always running full speed, making it very loud. I do have the smart CPU fan set to "enabled" in the BIOS. I flashed to a new BIOS, still no change. My temps are running 5-10 degrees C cooler then normal.

It is a Zalman CNPS9700LED. it only has a 3 pin connector, the motherboard is a 4 pin. However, the old board was also a 4 pin but it was able to control the speed.

Any tips? I am sick of hearing my fan! (and yes I am sure it is the CPU fan). When I look in the BIOS, it is running about 2800 rpm constantly.

 

[mpilchfamily]

If you want it slower then by a fan controlr and connect the CPU cooler to it. Not all boards support the ability to control the 3 pin fans. Those that are PWM boards may only control those fans and not have the ability to control the 3 pin fans. Each kind of fan uses a diffrent method to control its speed.

 

[Zap]

Originally posted by: mpilchfamily
Not all boards support the ability to control the 3 pin fans.

That's the problem, in a nutshell.

I recently encountered this problem with some MSI motherboards (using 750a SLI chipset, forgot which exact model). The solution was to plug the CPU fan into one of the chassis fan headers because the BIOS allowed one 3 pin header to be controlled as well (really rough, 25%/50%/75%/100%). See if your BIOS has that feature.