User’s Guide
BIOS Setup
4-29
When HDD type is in ‘user’ type, the ”MODE” option will be opened for user
to select their own HDD mode.
(2) HDD Modes
The Award BIOS supports 3 HDD modes : NORMAL, LBA & LARGE
NORMAL mode
This is the generic access mode in which neither the BIOS nor the IDE
controller will make any transformation during accessing.
The maximum number of cylinders, head & sectors for NORMAL mode
are 1024, 16 & 63.
no. Cyclinder
(1024)
x no. Head
( 16)
x no. Sector
( 63)
x no. per sector ( 512)
528 Megabytes
If a user set his HDD to NORMAL mode, the maximum accessible HDD
size will be 528 Megabytes even though its physical size may be greater
than that.
LBA (Logical Block Addressing) mode
This is a new HDD accessing method to overcome the 528 Megabyte
bottleneck. The number of cylinders, heads & sectors shown in setup
may not be the number physically contained in the HDD.
During HDD accessing, the IDE controller will transform the logical ad-
dress described by sector, head & cylinder number into its own physical
address inside the HDD.
The maximum HDD size supported by LBA mode is 8.4 Gigabytes whi-
ch is obtained by the following formula:
no. Cyclinder
( 1024)
x no. Head
( 255)
x no. Sector
( 63)
x bytes per sector
( 512)
8.4 Gigabytes
