When choosing parameters for the minimum and maximum fan speed, try to set them by hand (disable all the VARIATE FANs checkboxes) and listen to the noise. By properly configuring SpeedFan, you can let it change fan speeds based on system temperatures.

SpeedFan monitor temperatures from several sources. PWM4 and PWM5 on ITE IT8620E are now disabled by default (please, read this article). ITE IT8620E (used on several Gigabyte boards) support has been greatly enhanced (now SpeedFan can control up to 5 fans and report voltages too). This version defaults to no SCSI access if the Intel Storage Driver is found. SpeedFan 4.51 Final is now online! It adds support for a lot of new hardware. SpeedFan works fine with Windows 9x, ME, NT, 2000, 2003, XP, Vista, Windows 7, 2008, Windows 8 and Windows Server 2012. SpeedFan can access digital temperature sensors and can change fan speeds accordingly, thus reducing noise.

SpeedFan can even change the FSB on some hardware (but this should be considered a bonus feature). SpeedFan is a program that monitors voltages, fan speeds and temperatures in computers with hardware monitor chips.

Speedfan 4.52 final