You need four-pin PWM (pulse wave management) connections from the fans to the motherboard. This is for chassis or CPU fan speed management just FYI. If you only have three-pin chassis fan connectors to the motherboard, you can't control through the motherboard BIOS/software utility program. My Antec Nine Hundred chassis fan connectors are not PWM but they do offer manual dongle switches for all fans for three speed settings (low, med, high).