I know there are fans out there that have a dedicated PWM input, but I like to know if I can PWM control a fan that does not have such a dedicated PWM input. So...
If I have a 3 pin 12v fan like the Noctua NF-A20 with connections:
- 12 V
- tach out (RPM measurement)
Can I control its speed by PWM on the 12V supply voltage (using a MOSFET most probably)? Would the tach out still work?