Fan wiring

[kevbiss1]

just fitted my old cpu cooler(pwm)as a system fan,through a fan controller and onto my mobo for monitoring purposes,i had to leave the blue wire unconnected as the red,black and yellow wires matched up with the fan controller lead, what can i do to get readings on cpuid hardware monitor?
dont fancy trial and error and blowing stuff up!
the fan works fine
can someone tell me what the 4 wires do

 

[Mick-1965]

Red and black are the supply voltage.
Yellow is the RPM sense wire
Blue is PWM(pulse width modulation) speed control wire

Without the blue PWM wire the fan will run as a normal 3 wire fan but at full RPM

 

[kevbiss1]

ok, thanks, thats helpful to know what wires do what,i think my solution is basically to run a 3 wire fan, but i think ill leave it as it is because of the extra cooling i get with the cpu fan