You configure the capability through BIOS Setup (Visual BIOS), but an embedded microcontroller (within the Super I/O (SIO) ASIC) actually implements the fan speed control.
Hope this helps,
Intel Extreme Tuning Utility may do what you want, but use caution when using it as it directly modifies BIOS entries and its a little wonky...
https://downloadcenter.intel.com/download/24075/Intel-Extreme-Tuning-Utility-Intel-XTU- Download Intel® Extreme Tuning Utility (Intel® XTU)
Thanks. I'll try that and the BIOS way I've nothing against using the BIOS, it's just I don't like rebooting my machine too often. Got so many scripts and whatever running. Cheers.