speednfs :
Sorry for dump questions but why are good brands better and how do you mean protect my PC I don`t get it..?
For example, if there are power variation, a cheap PSU can easily go bang. (and possibly fry other components). Cheap ones don't have overload protection, and ussualy the real Wattage is lower than the one written on it. My opinion, and I can tell you that from my own experience with firecracker PSUs.