I recently built my first PC, and for the most part had no idea what I was doing. During the building process I notices that my motherboard only had 3 case fan headers while I had 5 case fans. So for a while I simply let 2 fans do nothing, until I decided to go in and do some cable management. I plugged the two fans into a molex header, then into my PSU (the two fans' cables consolidate into one wire with a molex connector at the end and another wire coming out of it that is a standard 3 pin fan header). To my dismay, this setup isn't working . It's possible that there is something very simple I've overlooked, but if you can, please help.