This is my GUESS too, if the ballast gives enough juice at start up to get it going.If I had to guess I would say the 96 watt bulb would run at about 65 watts in that fixture and would look dimmer than usual. But, I doubt that it would overheat. If you put a 36 watt bulb in the fixture, that bulb would overheat, be overdriven, and probably have a very limited life. I may be very wrong about this though.