I'm gradually building a new 3d printer with a smoothieboard to control it, and I'm getting confused by how to wire up a PWM controlled cooling fan and what the switch module settings really mean. First, fans themselves are confusing me. There are 4 pin fans with one pin for a PWM control signal. Do I need one of those, if so, how the heck to I wire it up to the smoothie? Is that what the hardware pwm setting is for? Or am I completely overthinking and should just use a 2 or 3 pin fan on a small mosfet and let it do the PWM? Is that what the software pwm setting is for?