An(other) intelligent 4-wire fan speed controller – Matt's Tech Pages
4-Wired Fan Control (PWM) - Hackster.io
4-Wired Fan Control (PWM) - Hackster.io
Amazon.com: Taidacent 2510-4P 3P Manual 4 Wires 0-5V 12V Fan Speed Controller PWM Speed Control On Off Switch for PC CPU Case Fan with Knob (White Connector with Plastic Black Knob) :
Acquista 4-Wire High-Temp Fan Temperature Control Module DC 12V High-Temp Alarm Fan Speed Controller Module PWM PC CPU 50K | Joom
PWM control for 4-wire fans? - Motors, Mechanics, Power and CNC - Arduino Forum
PWM 4-Wire Fan Temperature Controller Speed Governor For PC Fan/Alarm DC 5V-12V | eBay