Advertisements So, when Comcast originally installed Cards in my tivo HD they left me with an M card and an S card incorrectly installed and not working. I fixed things with a couple of phone calls and the box has been working without too many problems for nearly 2 years. This leaves me with a spare S card and I am now thinking of buying another tivo to replace my lousy cable box. A bunch of questions for the experts: 1. How likely will the spare S card work in a new tivo for non-premium channels without having to call Comcast? (By "work" I mean correct channel guide and ability to tune all non-premium digital channels.) 2. If it works what will be the tivo's behavior? a) Will it behave as if it only has one tuner? b) Will it behave as if it had one digital/HD tuner and one analog-only tuner? c) Will it behave as if it had two digital tuners 3. Any other issues when using a single S card only? I am not trying to save money here but am very afraid that if Comcast has to show up for an installation then they will mess up my working tivo. Thanks for any feedback!!