Sure replace the fan, no problem, done it many a time. I like the Panasonic Panaflo Silent fans. Find them on Ebay. Your existing fan may be hard wired onto the circuit board of the PS. If so, just cut the wires and splice the wires of the new fan to the old wires. A little electrical tape, and you are done. Or, as others have mentioned, just replace the entire PS. Your choice.