This subject is as crazy as windows doing something common sense..
 But I ask frequently if one exists.
 I find the typical 3 speed controllables everywhere at the standard 80mm (is that not the oldest of pc fans?)
 anyway..The modern pwm controller for fan speeds is up to 8 different speeds on my mobo...and the fans were left back in 1987 forced to evolve with them unproperly. I have yet to find one.
 The freaky fan I have now goes to 4 speeds, by accident I am sure, as one rpm reporting stage is wrong and the mobo accepts it. That is the catch with the fan speeds..
 With a prog like speedfan, I can get the fan quiet a gentle curve rheostatically.. with worng rpm reported. Why have it half assed?
 I need a modern standard size 80mm fan that will top out at say 2400 (.16A) and slow way down to like 900 or 1000, split across 8 different speeds on auto...ahh that would be cpu fan heaven.