User's Manual 71
2. HDD Modes
The 541 Award BIOS supports 3 HDD modes : NORMAL, LBA & LARGE.
( I ) NORMAL mode
Generic access mode in which neither the BIOS nor the IDE con-
troller will make any transformations during accessing.
The maximum number of cylinders, head & sectors for NORMAL
mode are 1024, 16 & 63
no. Cylinder
(1024)
x no. Head
( 16)
x no. Sector
( 63)
x no. per sector
( 512)
528 Megabyte
If 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!
( II ) LBA (Logical Block Addressing) mode
A new HDD accessing method to overcome the 528 Megabytes
bottleneck. The number of cylinders, head & sectors shown in setup
may not be the number physically contained in the HDD.
During HDD accessing, the IDE controller will transform the logi-
cal address 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
which is obtained by the following formula:
no. Cylinder
(1024)
x no. Head
( 255)
x no. Sector
( 63)
x no. per sector
( 512)
8.4 Gigabyte
