I have salvaged a PC fan from an old Dell Dimension E310. I was wondering what the color code was (except for + and -, obviously black and red)
One is tach output and the other is speed select.
thank you does the speed input use PWM?
Hi, try this site for a great explanation
it talks about the pwm issues, the speed input you refer to can be cut off to make a working 3 pin fan, it then leaves the gate of the fet floating, ie should turn on.
There is an Intel specification for PWM-controllable PC fans at Motherboard Form Factors and I have successfully controlled one of these from an Arduino. However, I think Dell fans work to a different specification, which I've never seen published.
Okay i used the example sketch AnalogInOutSerial, but the fan stayed at full blast =(