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The Complete Guide on FAT 32 |
FAT32
A new version of the file allocation table (FAT) available in Windows
95 OSR 2 and Windows 98. FAT32 increases the number of bits used to address
clusters and also reduces the size of each cluster. The result is that
it can support larger disks (up to 2 terabytes) and better storage efficiency
(less slack space).
An Enhanced File System for Windows 95
PC Magazine tutorial article on what FAT32 does to solve problems with
the old FAT, and other advantages and disadvantages of the new file system.
Updated on Aug 4, 1998
http://www.zdnet.com/pcmag/pctech/content/16/07/os1607.001.html
Follow the "Next Article".
FAT32 Resource Page
This site explains all the options and specifications of the new FAT32
file system for Windows. This page has been created to help answer some
of the questions and confusions about FAT32 and its new features. Updated
on Aug 4, 1998
http://www.project9.com/fat32/
Partitioning Your Hard Disks
PC Magazine tutorial article on how to squeeze extra storage out of
large capacity drives with more efficient partitions. Provides very good
background information as well as an explanation of FAT32. Updated on Aug
2, 1998
http://www.zdnet.com/pcmag/pctech/content/16/11/tu1611.001.html
Everything you need to know about OSR2 and FAT32
Detailed FAQ about OSR2 and FAT32. The page is maintained by Sean Erwin.
Updated on Aug 5, 1998
http://www.flash.net/%7Ehollowel/pro/fat32/index.html
Files Systems FAQ
Describes how to manage partitions and directories and includes general
information about Windows NT and links to useful utilities.
http://www.mountainmicro.com/NTFAQ/ntfaq/filesystems.html
Microsoft Knowledge Base article on FAT32
This article describes the FAT32 file system included with Windows
95 OEM Service Release 2 (OSR2). Updated on June 25 1998
http://support.microsoft.com/support/kb/articles/q154/9/97.asp
Problems Accessing FAT16 Drives Larger Than 2 GB
http://support.microsoft.com/support/kb/articles/q127/8/51.asp
Windows 95 OSR2 and Windows 98 include an updated version of the File Allocation Table file system, called FAT32. This updated file system allows for a default cluster size as small as 4K, as well as support for EIDE hard disk sizes in excess of 2 GB.
Features
FAT32 provides the following enhancements over previous implementations of the FAT file system:
Supports drives up to 2 terabytes in size.
NOTE: Although FAT32 supports drives up to 2 terabytes in size, drives may not be larger than 7.8 GB due to limitations of the BIOS INT13 interface. Uses space more efficiently.
FAT32 uses smaller clusters (that is, 4K clusters for drives up to 8
GB in size), resulting in 10 to 15 percent more efficient use of disk space
relative to large FAT16 drives.
More robust.
FAT32 has the ability to relocate the root directory and use the backup
copy of the FAT instead of the default copy. In addition, the boot record
on FAT32 drives has been expanded to include a backup of critical data
structures. This means that FAT32 drives are less susceptible to a single
point of failure than existing FAT16 volumes.
More flexible.
The root directory on a FAT32 drive is now an ordinary cluster chain, so it can be located anywhere on the drive. For this reason, the previous limitations on the number of root directory entries no longer exist. In addition, FAT mirroring can be disabled, allowing a copy of the FAT other than the first one to be active. These features allow for dynamic resizing of FAT32 partitions. Note, however, that while the FAT32 design allows for this capability, it will not be implemented by Microsoft in the initial release.
Compatibility Considerations
In order to maintain the greatest compatibility possible with existing programs, networks, and device drivers, FAT32 was implemented with as little change as possible to Windows's existing architecture, internal data structures, Application Programming Interfaces (APIs), and on-disk format. However, because 4 bytes are now required to store cluster values, many internal and on-disk data structures and published APIs have been revised or expanded. In some cases, existing APIs will not work on FAT32 drives. Most programs will be unaffected by these changes. Existing tools and drivers should continue to work on FAT32 drives. However, MS-DOS block device drivers (for example, ASPIDISK.SYS) and disk tools will need to be revised to support FAT32 drives.
All of Microsoft's bundled disk tools (Format, FDISK, Defrag, and MS-DOS- based and Windows-based ScanDisk) have been revised to work with FAT32. In addition, Microsoft is working with leading device driver and disk tool vendors to support them in revising their products to support FAT32.
NOTE: A FAT32 volume cannot be compressed using Microsoft DriveSpace or DriveSpace 3.
Performance
Converting to the FAT32 file system is one of the biggest performance enhancements you can make to your Windows 98-based computer.
Dual-Boot Personal Computers
At this time, Windows 95 OEM Service Release 2 and Windows 98 are the only operating systems capable of accessing FAT32 volumes. MS-DOS and the original version of Windows 95 do not recognize FAT32 partitions, and are unable to boot from a FAT32 volume.
Windows 95 OSR2 and Windows 98 can still be booted to real mode (for example, to run a game) and can use FAT32 volumes.
NOTE: FAT32 volumes cannot be accessed properly if the computer is started using another operating system (for example, a Windows 95 or MS-DOS boot disk).
Creating FAT32 Drives
In OSR2 and Windows 98, if you run the FDISK tool on a system with a drive over 512 MB, it asks whether to enable large disk support. If you answer Yes, any partition you create that is larger than 512 MB is marked as a FAT32 partition.
Windows 98 also includes a FAT32 conversion tool that you can use to convert an existing drive to the FAT32 file system. To use the conversion tool, follow these steps:
1. Click Start, point to Programs, point to Accessories, point to System Tools, and then click Drive Converter (FAT32).
2. Click Next.
3. Click the drive you want to convert to the FAT32 file system, and then click Next.
4. Follow the instructions on the screen.
Support Boundaries
Microsoft will support the functionality of the FAT32 file system for error-free reading, and saving of files either in real mode or protect mode. We support the real- and protected-mode tools included with Windows 95.
For legacy programs that will not install on a FAT32 volume, or will not properly save files or read them, you will have to contact the manufacturer of the software package.
NOTE: Although the FAT32 file system supports hard disks up to 2 terabytes (TB) in size, some hard disks may not be able to contain bootable partitions larger than 7.8 gigabytes (GB) due to limitations of the basic input/output system (BIOS) INT13 interface. Please contact your hardware manufacturer to determine if your computer's BIOS supports the updated INT13 extensions.