Advertisements The discussion was about the WD 1TB OEM HDD: Model # WD10EACS-00ZJB0 being different than the WD 1TB Retail HDD: Model # WD10EACS-32ZJB0. Both drives became available last August. The later drive worked as an upgrade for both TiVo HD's and Series3's (I have one in our Series3), the former only worked in TiVo HD's due to soft reboot failures in the Series3's. Both can be used as eSATA drives for both TiVo models. The newer Western Digital AV GP 1TB DVR dedicated drives have been used to upgrade both the TiVo HD and Series3 models successfully. That's why they are recommended. The recommended drive is not the one the OP was talking about. What is confusing is why you would jump into a thread and make statements like that without knowing what you were talking about. Nuff said.