A CC I acquired was dead for quite sometime, and wouldn't turn on at all until I left the thing plugged into the wall with the master power (rear switch) on for two days, then hit keyboard button for soft power. Doesn't sound like that's exactly your problem, but if I were you try unplugging, cleaning and replugging in the drives that don't work and leave it soaking on those power mains for a good amount of time after that. I don't know a lot, but it doesn't seem like your PSU is shot based on what you're describing.