use a pot to control speed of the fan (via voltage limiting) and DONT PLUG THE FUCKER INTO A WALL PLUG wall plugs are AC comp fans are DC.. hit a thrift store for an appliance that runs off a dc powersource.. anything that has a big black box that plugs into the wall instead of just a normal cord.. and READ.. MAKE SURE IT SAYS DC thoes fans will take up to 14 ish volts.. if you find one that is higher you can use resisters.. (or a POTentiomiter) to reduce voltage to a usable voltage but double check it says DC not AC