to be honest, the "factory" power supplies are a real piece of junk. they are under powered and are run right to the limit so they run hot and fail easily. they are "rated" at 200 watts, but once they heat up to 35 or 40 degrees celsius. (commonly found inside these god forsaken cabinets) they are actually detrated to 130 watts and once you hit 50c, even less.
You really want to upgrade the supply to a 300 or 350 watt "ITX" power supply. you'll have to do some tweaking and hacking of the cables to get it to work (need to transfer a cable connector over), but trust me, it's going to be worth it in the long run. they have enough overhead that they run cooler and don't hit that derate temp.