What exactly MUST be done to a hard drive to make it "TIVO ready?" I think some kind of service registration is probably on the hard drive, but if its over a year old, there is no warrantee anyway - and how could this be put on a replacement drive anyway without the individual TIVO box in hand? As I understood it, TIVO downloads all the needed software (or updates the software you have) when you first use it or during it's regular programming updates. What actually HAS to be done to the drive? Anything? Also, if something unique/quirky IS done to a large replacement drive, does this mean a large drive is rendered worthless thereafter for use in a PC (reformatted)? What could someone put on a drive to render it worthless to PC reformatting??