IBM Deskstar 25GP Installation And Reference Manual page 63

operation. Your drive will function at the maximum speed supported by your system
components.
Certain BIOS and motherboard chipset combinations function incorrectly when the drive
reports a UDMA mode higher than the motherboard was designed for. Following is a list
of problems and solutions related to specific operating systems.
• Windows 95
When the system does not correctly switch to a compatible speed (i.e., ATA/33),
complete startup of Windows 95 may fail after enabling the Direct Memory Access
(DMA) feature in the Windows Control Panel.
• Windows 98
When the system does not correctly switch to a compatible speed (i.e., ATA/33),
complete startup of Windows 98 may fail after enabling the DMA feature in the
Windows Control Panel.
• Windows NT 4.0
The most common symptom is a failure to boot after a bus mastering driver has been
added and loaded.
Solutions
•
Obtain a new BIOS for the motherboard to correct the Ultra ATA/100 or Ultra ATA/66
detection problem.
•
Alter the Deskstar drive to report ATA/33 capability. IBM offers a tool called
IBMATASW.EXE to perform this alteration. Contact the IBM Hard Disk Drive
Technical Support Center for more information.
6. What is the difference between ATA/33 and Ultra ATA/66?
Ultra ATA/66 is an extension to the Ultra DMA interface. It doubles the ATA/33 interface
data transfer rate from 33 MB to 66 MB per second.
7. What is ATA/100?
ATA/100 is an extension of the Ultra DMA interface which enables data transfers as fast
as 100 MB per second.
8. What is the difference between FAT16 and FAT32?
FAT16 is limited to 2.1GB per partition. This file system is widely compatible with OS/2,
Windows NT 3.5 and 4.0. FAT32 allows a single partition to utilize the full drive capacity.
Some disk utilities and virus scanners published before 1997 are incompatible with
FAT32.
9. Do I need to create more than one partition on my IBM Deskstar?
Partition sizes are limited to 2GB in DOS, Windows 3.11 and Windows 95A due to the
FAT 16 file system design. You need to create multiple partitions to utilize full drive
capacity. If you are using Windows 95 SR2 or Windows 98 and FAT32, you may create
one partition to utilize the full drive capacity. FAT 32 partitions may be incompatible with
disk utilities and virus scanners published before 1997.
56