Recently some of my USB ports been playing up not recognising mass storage devices and then I noticed my SM Bus Controller had the little yellow exclamation mark on it in device manager. So I got the cd for the motherboard, made sure I was logged in as administrator and reinstalled the chipset drivers which have the SM bus driver included. No luck. Says 'driver installation file is missing a necessary entry'. Tried installing the SM Bus driver on it's own. Same problem. Got latest drivers from ASUS for the chipset. Same problem. Got drivers from Intel. Same problem. Tried safe mode. Same problem. Tried many other things...always same problem. Wondered if anyone has had a similair issue and can maybe help me out here. (Vista 64, ASUS P5Q-E).