Toshiba T5200 - Conner hard drives
At various places on the Internet, it is stated that the BIOS in the Toshiba T5200 can only use hard drives that have a reported model that starts with "CP" (i.e. Conner made drives).
An example is at here.
However, the information at here suggests that it isn't always the case. (See there the reference to the Award v5.3 BIOS.)