Check to make sure all chipset drivers are installed.
Does it say this when it restarts?
The fan is not connected to the FAN LED. fan stays on when FAN LED light turns off. The case is: COOLER MASTER HAF X RC-942-KKN1 Black Steel/ Plastic ATX Full Tower Computer CaseThe only reason I could think of that the fan would affect it at all is, that it is probably drawing too much power from the power supply. Or, if the fan is connected to the motherboard, it is probably taking too much power from the supplied power which would make your motherboard act strange. Be sure to check if the fan is not drawing too much power, you don't want to burn a part of your hardware out for a measly fan.