So after installing GTX 460 Hawk on my H61MU3, case fan isn't working. I think the mobo is not supplying power, but that just a hunch. Please share your opinions guys
first off double check the cable, maybe the connection (line) is disconnected somewhere, in case you got confused or something.
to check, post a picture maybe
Probably the power cable to the fan got knocked out of place. Try hooking it back into the motherboard, if that doesn't work connect the fan to your power supply.