Hi my power brick died so I bought a non original replacement and now it beeps, flashes white but turns off after the fan comes on. I've opened it up swapped the HDD but still the same. If I unplug the HDD it stays on a out 30 seconds longer so I'm wondering if it's a sub standard power brick. I'm going to fix the original power brick by replacing the blown caps but can anyone suggest what else the issue could be. Thanks, Andy