Tugboat

If it's a switching power supply, it needs to see a load on the 5v lines before it'll run. It's designed this way because running a switching power supply with no load is bad for the PS. To do this right, go to radio shack or someplace like that, and buy a 50ohm, 10 watt sandbar resistor and connect it from one of the 5V wires to one of the black (ground) wires. Zip tie it to the side of the PS case, and it's good to go. I've converted several PS's to stand-alone power units for my ham radio stuff and electronics. I can post the howto if anyone wants it.