I've lost the power supply that goes with my FreeAgent Desk 500GB external drive. While I think I can find a 12V, 2A supply lying around, I would love to put this inside of my tower. Worst case, I can utilize the USB interface with an internal USB port on an extension slot. How could I connect this drive to my tower's power supply? PS: I'm technically savvy, and a warranty voider.... I've already wiped the software preinstalled and opened the case. Soldering-involved solutions are even a viable route...