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Bios – Tyan Computer S1854 User Manual

Page 39

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S1854 Trinity 400

39

HARD DISKS

The BIOS supports up to four IDE drives. This section does not show

information about other IDE devices, such as a CD-ROM drive, or about other

hard drive types, such as SCSI drives. Note: We recommend that you select

type auto for all drives.

The BIOS can automatically detect the specifications and optimal operating

mode of almost all IDE hard drives. When you select type auto for a hard

drive, the BIOS detects its specifications during POST, every time the system

boots. If you do not want to select drive type auto, other methods of selecting

the drive type are available:

1. Match the specifications of your installed IDE hard drive(s) with the

preprogrammed values for drive types 1 through 45.

2. Select User and enter values into each drive parameter field.

3. Use the IDE HDD Auto Dectection function in Setup.

Here is a brief explanation of drive specifications:

Type: The BIOS contains a table of pre-defined drive types. Each defined drive

type has a specified number of cylinders, number of heads, write

precompensation factor, landing zone, and number of sectors. Drives whose

specifications do not accommodate any pre-defined type are classified as type

user.

Size: Disk drive capacity (approximate). Note that this size is usually slightly

greater than the size of a formatted disk given by a disk-checking program.

Cyls: Number of cylinders

Head: Number of heads

Precomp: Write precompensation cylinder

Landz: Landing zone

Sector: Number of sectors

Mode: Auto, Normal, large, or LBA

Auto: The BIOS automatically determines the optimal mode.

Normal: Maximum number of cylinders, heads, and sectors

supported are 1024, 16, and 63.

Large: For drives that do not support LBA and have more than 1024

cylinders.

LBA (Logical Block Addressing): During drive accesses, the IDE

controller transforms the data address described by sector, head, and

cylinder number into a physical block address, significantly

improving data transfer rates. For drives with greater than 1024

cylinders.

BIOS