Adding to what catdog has said as well as checking the drive end, also check the IDE cable is seated correctly into the mainboard, and the power cable for the drive is seated correctly into the PSU.

The TiVo will not work with the drive jumper set to cable select. It must be set to master for a single drive system. Some newer drives have different jumper settings for master depending on whether or not a slave is attached, make sure you use the correct setting.

A badly imaged drive is also possible, though I would have thought you would have seen an error message during the setup.

Peter.