Then it's probably a Molex connector. You can buy an adapter or get another fan. Here is a list of fans that you can use to directly mount to your motherboard or even a after market fan controller. Google the difference between molex fan connectors, 3 pin fan connectors, and 4 pin fan connectors. When you see the difference in not only the connection you will also see there is a small difference in the 4 pin as well. Usually its just a speed variable for readouts on the motherboard. knowing the pin-out and what each wire is fore helps. You can also change those connectors out with a bit of easy modding. Let me know if you need anymore help
http://www.newegg.com/Product/Product.aspx?Item=N82E16835103073&cm_re=200mm_fan-_-35-103-073-_-Product
http://www.newegg.com/Product/Product.aspx?Item=9SIA7B42W01788&cm_re=200mm_fan-_-35-129-065-_-Product
http://www.newegg.com/Product/Product.aspx?Item=N82E16835106248&cm_re=200mm_fan-_-35-106-248-_-Product