Ok :-) Now that I've introduced SpeedFan, please, let me tell you a few words... Developing SpeedFan has required (and still requires) really *a lot* of work. Running this website, answering emails, hunting for datasheets, purchasing hardware... It all requires a lot of work :-)
SpeedFan is freeware. You can use it without paying anything.
Anyway: if you feel a donation would be a nice way to support SpeedFan and its improvement over time, it will be appreciated :-)

If you can't find it, feel free to do multiple payments to reach to amount you like ;-)