Constantine Aleksandrovich Murenin posted his work on fan control, involving Winbond Super I/O Hardware Monitors. He’s had a series of commits up to this point, and this message nicely sums up the work done, including the presentations for it at BSDCan last year and AsiaBSDCon this year. Even if you aren’t planning to adjust your system cooling, it’s a surprisingly in-depth writeup, with more details available.