Vig550B Motherboard Manual – Ver 1.0
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Auto Detected allows the BIOS to examine the drive and determine the optimal
mode. The first choice is to utilise Logical Block mode if it is supported by the drive.
The second choice is to utilise Extended CHS mode if the drive topology allows. If
neither of the above methods is possible, the Standard CHS mode is used.
Different operating systems have different abilities regarding IDE translation mode.
UNIX operating systems (as currently implemented) do not support either LBA or
ECHS and must utilise the standard CHS method. UNIX can support drives larger
than 528MB, but does so in its own way.
OS/2 2.1 and OS/2 Warp can support LBA, ECHS or standard CHS methods. Note
that LBA support may require a switch setting on an OS/2 driver in order to operate
in that mode.
OS/2 2.0 & Novel NetWare can support either ECHS or standard CHS methods. In
order to use LBA with NetWare a driver that supports current parameters must be
used.OS/2 2.0 does not support LBA.
DOS & Windows can use LBA, ECHS or standard CHS methods. The '32-bit Disk
Access' driver built into Windows WDCTRL.386 can only be used with the standard
CHS method, To use either LBA or ECHS method and '32-bit Disk Access' an
alternative .386 driver must be installed, this combination will also provide the best
performance. If this driver is not installed and the drive fitted to the system supports
Type F DMA on the ISA interface or Mode 3 on the PCI interface then higher
performance will be achieved by NOT using '32-bit Disk Access'.
