I need a power supply for an Athalon 1600 system I'm assembling. It will be running 2 hard drives (maybe a third eventually) and 2 cd drives. What kind of power rating do I need? And who makes good, inexpensive power supplies? I don't want anything fancy or expensive, just reliable, and preferably with a quiet fan since the system will be going in a bedroom. This is a budget system so I'd rather not spend any more than I have to.