I have 3 YL 120 HL's on a 360 rad. They have a direct power source that is getting a full 12v but they do not spin at full speed anymore Sure, they're quite, but I need some airflow. They started doing this after I hooked up a fan controller and the mosfet/transistor or what ever that thing was call blew because it could not handle that much current. Now, they spin at very slow speeds. Looks like about 600rpm. It's barely enough to push air through the rad. What happened and how can I fixed this?