They're both series 2 dtivos, so I believe you should be able to transplant a hacked drive from one to another. You'll probably have to run 51killer, but as long as you don't have any recordings from before you hacked the drive, you should be golden. Actually, to verify that all of your recordings aren't encrypted, you should probably run ciphercheck before you run 51killer.
DVR39 drive into a DVR40
My DVR39 bit the dust. Have tried a new powersupply and get the same clicking sound as I did with my old power suppy. The drive will spin if I disconnect the white cable from the power supply to the main board. So I am assuming that the main board is dead because when I plugg it back in nothing will power up and I just hear the clicking from the power supply. So if I get an old DVR 40 that a friend has can I put my upgraded and hacked drive from my DVR39 into the DVR40 or will I need to redo the drive as one for a DVR40? 
