UPGRADING REPAIRING PCs

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Chapter 4—SCSI and IDE Hard Drives and Optical Drives
overcome without changing to a different type of drive (SCSI) or
making the move to Windows 9x/2000/Me.
Even if you have updated versions of operating systems that support
IDE capacities beyond 8.4GB, your BIOS must also offer this
support. Table 4.7 describes the differences between how LBA and
Extended Int13h drive support work.
Table 4.7 LBA Mode Versus Extended Int13h
Mode Setting BIOS Drive Capacity Listing
LBA Must be set in BIOS by Indicates full capacity of drive;
user or automatically by might or might not indicate
drive-type detection. translation in BIOS.
Extended Automatically enabled BIOS configuration might or
Int13h when LBA mode is might not indicate full capacity
enabled on systems that
support Extended Int13h
functions.
of drive.
This support is not “visible” in the BIOS; there is no Enhanced
Int13h option to enable as there is with LBA mode.
Also, in some cases, the geometry reported by drives of varying
sizes doesn’t change either. On a system that supports Extended
Int13h but doesn’t display the full drive capacity in the BIOS configuration,
an 8.4GB hard disk will report a geometry to the BIOS
of 16 heads, 16,383 cylinders, and 63 sectors per track, and a
20.4GB hard disk reports the same geometry! Support of hard disks
beyond 8.4GB on some systems breaks the usual rule about the
BIOS configuration matching the drive’s capacity.
As with the previously mentioned LBA mode issues, use FDISK to
determine whether your system supports your greater-than-8.4GB
IDE hard drive at full capacity.
Drive Capacity Issues in Microsoft Windows 95 and 98
Table 4.8 lists the capacity limitations and issues for Windows 95
and 98.
Table 4.8 Drive Capacity Issues for Windows 95 and 98
Windows Drive Capacity
Version Limitation Fix
Windows 95 32GB None; upgrade to Windows 98, NT,
(all releases) 2000, or Me before installing larger hard
drive.
See Microsoft online document Q246818
for details.