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The tables were built using the parameters for various real hard drives. For example, type 1 is used for the original Shugart drives used in the PC XT (ST506). So the intention was for the drive types to be useful, and at least some of them were; in the linked page, scroll down to the list of Award-486 drive types to see more examples.

Each BIOS manufacturer had a list, as can be seen in the page linked above. The first 14 entries came from the PC AT’s BIOS, the rest varied although various settings show up in common across different BIOSes. The list of drives would change from one generation of BIOS to another, sometimes even from on BIOS revision to another; but all clones running the same BIOS version could be expected to have the same list of drive types.

The end of the table came when drives acquired the ability to report their own geometry; that allowed the users to set everything to “auto” (although setups still had to allow manual entry for a long time, to support older drives).

The tables were built using the parameters for various real hard drives. For example, type 1 is used for the original Shugart drives used in the PC XT (ST506). So the intention was for the drive types to be useful, and at least some of them were; in the linked page, scroll down to the list of Award-486 drive types to see more examples.

Each BIOS manufacturer had a list, as can be seen in the page linked above. The first 14 entries came from the PC AT’s BIOS, the rest varied although various settings show up in common across different BIOSes. The list of drives would change from one generation of BIOS to another, sometimes even from on BIOS revision to another; but all clones running the same BIOS version could be expected to have the same list of drive types.

The end of the table came when drives acquired the ability to report their own geometry; that allowed the users to set everything to “auto” (although setups still had to allow manual entry for a long time, to support older drives).

The tables were built using the parameters for various real hard drives. For example, type 1 is used for the original Shugart drives used in the PC XT (ST506. So the intention was for the drive types to be useful, and at least some of them were.

Each BIOS manufacturer had a list, as can be seen in the page linked above. The first 14 entries came from the PC AT’s BIOS, the rest varied although various settings show up in common across different BIOSes.

The end of the table came when drives acquired the ability to report their own geometry; that allowed the users to set everything to “auto” (although setups still had to allow manual entry for a long time, to support older drives).

The tables were built using the parameters for various real hard drives. For example, type 1 is used for the original Shugart drives used in the PC XT (ST506). So the intention was for the drive types to be useful, and at least some of them were; in the linked page, scroll down to the list of Award-486 drive types to see more examples.

Each BIOS manufacturer had a list, as can be seen in the page linked above. The first 14 entries came from the PC AT’s BIOS, the rest varied although various settings show up in common across different BIOSes. The list of drives would change from one generation of BIOS to another, sometimes even from on BIOS revision to another; but all clones running the same BIOS version could be expected to have the same list of drive types.

The end of the table came when drives acquired the ability to report their own geometry; that allowed the users to set everything to “auto” (although setups still had to allow manual entry for a long time, to support older drives).

The table was built using the parameters for various real hard drives. For example, type 1 is used for the original Shugart drives used in the PC XT (ST506. So the intention was for the drive types to be useful, and at least some of them were.

The end of the table came when drives acquired the ability to report their own geometry; that allowed the users to set everything to “auto” (although setups still had to allow manual entry for a long time, to support older drives).

The tables were built using the parameters for various real hard drives. For example, type 1 is used for the original Shugart drives used in the PC XT (ST506. So the intention was for the drive types to be useful, and at least some of them were.

Each BIOS manufacturer had a list, as can be seen in the page linked above. The first 14 entries came from the PC AT’s BIOS, the rest varied although various settings show up in common across different BIOSes.

The end of the table came when drives acquired the ability to report their own geometry; that allowed the users to set everything to “auto” (although setups still had to allow manual entry for a long time, to support older drives).