Well, I'm no expert on power supplies, but I don't think replacing one cheap no-name power supply with another is the right thing to do, even if it has more watts. The cheapest good brand power supply on Scan is the CX400, which is a little more money, but is a basic-but-good power supply from a well-respected company. It easily has enough power, is fairly quiet, and is less likely to fry your expensive other components.