Can I control two more PWM fans by a CPU PWM header using the signal wire, yet power them separately? I don't have room for a hub. As far as I understand, pins #1 & #2 are 12V power, #3 is RPM and #4 is PWM signal that is sent to an IC built into the fan. The only issue I see is if that signal is "read" differently from fan to fan. Anyone tried this?