QDI P6I440EX/MATX EXCELLENT II, Manual

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AWARD BIOS Description
3 - 16
Drive C: User(516MB) 1120 16 65535 1119 59 Normal
Drive D: None(203MB) 684 16 65535 685 38 ---------
When the HDD type is set as “user” type, the “MODE” option will be opened for
users to select their own HDD mode.
2. HDD Modes
The Award BIOS supports 3 HDD modes: NORMAL, LBA and LARGE, also Auto
detect.
NORMAL
Generic access mode in which neither the BIOS nor the IDE controller will make any
transformation during accessing. The maximum number of cylinders, heads and
sectors for NORMAL mode are 1024,16 and 63.
If the user sets 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
A new HDD accessing method to overcome the 528 Megabyte bottleneck.
The number of cylinders, heads and sectors shown in setup may not be the number
physically contained in the HDD.
During HDD accessing, the IDE controller will transform the logical address
described by the sector, head and cylinder number into its own physical address
inside the HDD. The maximum HDD size supported by LBA mode is 8.4 Gigabytes.
LARGE mode
Some IDE HDDs contains more than 1024 cylinder without LBA support (in some
cases, users do not want LBA). The Award BIOS provides another alternative to
support these kinds of HDD.
BIOS tricks DOS (or other OS) so that the number of cylinders is less than 1024 by
dividing it by 2. At the same time, the number of heads is multiplied by 2. A reverse
transformation process will be made inside INT13h in order to access the right
HDD
address.
Auto detect
If using Auto detect, the BIOS will automatically detect the IDE hard disk mode and
set it as one of the three modes.
3. Remark
To support LBA or LARGE mode regarding HDDs, there must be some softwares
involved which are located in Award HDD Service Routine (INT13h). It may fail to
access a HDD with LBA (LARGE) mode selected if you are running under an
Operating System which replaces the whole INT 13h.