I purchased 3 ARCTIC COOLING AF12025 PWM 120mm Case Fans to daisy chain on SYS_FAN2 as intake fans, set the BIOS on PWM fan control but no go. You can feel that the fan is almost getting enough power to turn but will not keep spinning on its own. Also no go if don't daisy chain and use only one fan. The CPU PWM fan works as it should, regulated by the CPU temperature. If I plug an ARCTIC COOLING PWM case fan into the CPU PWN outlet, it works fine. The fan instructions say if the fan turns less than 1000rpm, don't use it daisy chained. So, where is the sensor that controls SYS_FAN2 and how does it work? I can find no other control in the BIOS other than set fan mode to 'auto' or 'PWM', which I set to 'PWM', and the CPU PWM fan woks fine. This is not a big issue, I just wanted my intake fans to be quiet when system temp is low, but if I wire them PWM they don't seem to work at all.