Re: power problem
Well you're definitely not stressing any of your rails with that setup. I had a similar problem with the computer where it kept doing what you describe, turning on for a second and then restarting over and over again until it turned on. It turns out that one of my Molex connectors behind a bunch of other wires was lose and causing the system to short. After I rewired it and put a zip tie on it to make sure it didn't come apart I haven't had the problem again. If you don't notice any lose connections you might have a failing PSU, if it's still under warranty I'd replace it.
Maybe I'm a Lion...