web page matching your request. It is possible you typed the address incorrectly, or that the pageAs an option, you may visit any of the pages below for information about Western Digital services and products.Cause - AC power applied prior to connecting DC power If the PC is plugged in but there is no response from the power button, the External Power Supply may not have been plugged in correctly. Try the following 4 steps first: 1. Disconnect the External Power Supply from both the power and the PC. 2. Now clear the CMOS for the unit; further instructions for this process can be found in the product manual or by clicking on the model-specific related link. 3. After waiting a few seconds, plug the DC end in first; this is the end that plugs into the computer. 4. Then plug the AC end into the power source; the machine should now come up. If the PC still does not power up, other things to try: Connect a different External Power Supply from the same model of PC.