Defining IDE and ESDI disk geometry in the BIOS

The geometry of IDE or ESDI disks is stored by the BIOS in CMOS or parameter RAM. If this information is either not present in the first place, or is lost due to the failure of the on-board battery, you must enter the disk drive type or disk geometry information using the setup program supplied with the computer. Check your computer hardware reference manual for the appropriate ROM table entries or drive type for your computer.