I don't know how you have tested these fans, but I use AC and Coolink fans for years. AC F12Pro PWM and Coolink SWiF2 120P (I know you haven't tested them, but i can't understand why) produce a quite notable airflow at top RPM (1500 and 1700) of course with some noise. (and the AC Pro series is more quiet and has bigger airflow in fact than the regular one) Everything has a price, but because of the fact they are PWM controlled, in most of the cases they are actually noiseless. Not to mention the unique advantage of PWM sharing technology of AC PWM fans.
Ps.: And the extra yellow cable is to report the RPM to the motherboard through another even regular 3-pin connector, not to share the PWM signal, that's the blue one.
02/10/11 11:16:35 AM]