PWM Fan - can it run directly off 3.3v, 5v or 12v inputs/GND?

[Trash80toHP_Mini]

I've got a case with 3 PWM fans and an incompatible (Beige G3) logic board. I'd like two fans to run off a power level a step below the third in any combination of the three voltages available on an ITX PSU.

Does this amount to a simple hotwire kluge or do they need a controller to function?

 

[luRaichu]

Does this amount to a simple hotwire kluge

Yes. Just hook up the red wire to your voltage and the black wire to ground