LBA Mode Control
When enabled, this option allows the System BIOS to reference hard disk data as logical blocks
instead of using the traditional Cylinders/Heads/Sectors (CHS) method. This option can only be
used if both the hard disk being configured and the operating system support Logical Block
Addressing (LBA). If disabled, then CHS mode is used. Note that autotyping may change this
value if the hard disk reports that it supports LBA. The default is Disabled.
32-Bit I/O
This option allows the System BIOS to access the hard disk controller with 32-bit I/O accesses,
increasing system performance, This selection is not affected by autotyping. If the PCI IDE con-
troller in the chipset is being used, then this option should be set to Enabled to maximize system
performance. If an ISAbus IDE controller is installed in the system, then this option should be
set to Disabled. The default is Disabled.
Transfer Mode
This option selects the mode that the System BIOS uses to access the hard disk. The selections
are: Standard, Fast PIO 1, Fast PIO 2, Fast PIO 3, and Fast PIO 4.
Older hard disks only support Standard. Newer hard disks adhering to Fast ATA or Enhanced
IDE specifications may support the fast programmed I/O or DMA modes. Note that autotyping
may change this value depending on the transfer modes that the hard disk supports. The fast
DMA modes take full advantage of the onboard bus master hard disk controller and yields the
highest performance when used in conjunction with multitasking operating systems that support
it. The default is Standard.
Ultra DMA Mode
This option selects the Ultra DMA Mode that the System BIOS uses to access the hard disk. The
selections are: Disabled, Mode 0, Mode 1, and Mode 2. The default is Disabled.
USB Legacy Support
This option allows for USB support of non-USB supported operating systems. Enabling of this
option can cause system conflicts with operating systems that support USB. The default is
Disabled.
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