post #21 of 21
Pwm fans run a constant 12v power with their signal from the mobo to ramp them up or down, not by changing the voltage. Using a 12v molex from psu will not cause them to be full speed all time. Your mobo will send the signal to do that on demand. Use the splitters and the psu to power them.

I have 4 pwms slitting off one 4pin mobo fan connection and have no issues