Grumpy_Mike:
But if they use PWM instead how do they control fans that does not have PWM support?
No all motors will respond to PWM, do you understand it?:-
PWM
If they don't regulate voltage then how do they control it as in what kind of component?
I do know how PWM works. The fan does not have natively support for PWM (the fourth pin for control input) so to use PWM would require a component and would that be better then voltage regulation?
I have only seen the fan been controlled by fan controller (like the Lamptron Fan Controller FC5V2) that regulates the voltage, at least that is what I assume since, like the Lamptron, there is not one word about PWM in the specifications and they take a 3pin connector for the fans, where as a PWM fan has a 4pin connector.