On Sunday, August 22, 2021 09:41:59 AM to...@tuxteam.de wrote: > On Sun, Aug 22, 2021 at 09:03:51AM -0400, Polyna-Maude Racicot-Summerside > > Like I already wrote, modifying voltage doesn't change speed of a motor > > (fan). > > I disagree. The thing poses [1] as a DC motor (2 pins power, one tacho). > I don't think you get too much control over RPM, but putting the tacho > in the control loop should be possible.
+1. A voltage controlled DC (computer fan) motor can be controlled / regulated down to about 40% of full rated speed (depending on the motor). A PWM (computer fan) motor can be controlled down to about 20% of full rated speed. > I have no idea what the motherboard/fan manufacturers actually do, though. I know that at least some motherboards (perhaps only older ones?) controlled fan speed via voltage control. > [1] I'm nearly certain it's a BLDC in disguise, with some electronic goo.
