not sure on this but i think I read somewhere that the 680 puts out 4 volts and the 6800 puts on 2... i think
i only bought the 680 because the name was shorter so I didnt have to type as much in my signature since this was my first h/u and had no idea what 2 and 4 volts meant //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif