Differences between FAT16 and FAT32

Before explaining the FAT file system, we must know what FAT is? "File Allocation Table" means "File Allocation Table. As the name suggests, it is a table used to record the location of a file. It is very important for hard disk use. If the file allocation table is lost, the data on the hard disk cannot be located and cannot be used. Different operating systems use different file systems, commonly used in the personal computer operating system, MS-DOS 6. FAT16 is used for versions x and below; HPFS is used for OS/2; NTFS is used for Windows NT; and FAT16 and FAT32 are also provided for users in MS-DOS 7.10 and ROM-DOS 7.10. Among them, we have the most contact with FAT16 and FAT32 file systems.
I. FAT16 File System
FAT16 uses a 16-bit space to represent the configuration file of each Sector (Sector), so it is called FAT16.
FAT16 is inherently limited. Therefore, after a partition exceeds a certain capacity, the Cluster size used by FAT16 must be expanded to accommodate larger disk space. The so-called cluster is the configuration unit of the disk space, just like a shelf in the library. Each file to be saved to the disk must be configured with a sufficient number of clusters. The relationship between each FAT16 partition and the cluster size is shown in the following table:
Partition size FAT16 cluster size
16 MB-127 MB 2 kb
128 MB-255 MB 4 kb
256 MB-511 MB 8 KB
512 Mbit/s-1023 Mbit/s 16 KB
1024 MB-2047 MB 32 KB
If you store 50 kb files in a MB partition, because the size of the partition cluster is 16 KB, it requires 4 clusters. If it is a 1 kb file, it must also be stored in a cluster. Can the remaining space in each cluster be used? The answer is no, so when using a disk, it will inevitably lose some disk space.
The FAT16 file system has two major disadvantages:
(1) The maximum disk partition size is 2 GB. At present, as long as you purchase a computer, the size of the hard disk must be at least 2 GB, and 3.2 GB, GB or more hard disks are everywhere, and inexpensive. The FAT16 file system is no longer able to adapt to the current large-capacity hard disk, and must be partitioned into several disk spaces. The size of the partitioned disk involves the issue of clustering, which is quite influential.
(2) The cluster size is inappropriate. Imagine that if a file of only 1 kb is stored in a MB disk partition, the space occupied is not 1 kb, but 16 KB, which is a waste of 15 kb! Currently, most popular HTML files are 1 kb and 2 kb in size, while dozens of HTML files are often used to create a website. If your hard disk contains 100 such small files, you can waste disk space from 3.1 kb (MB partition) to MB (MB partition ).
These two problems often make the user's choice of "how much partition to save space and make the hard disk more convenient and effective.
Ii. FAT32 File System
To solve the problem of FAT16, A FAT32 system is developed. FAT32 uses a 32-bit space to represent the configuration file of each Sector (Sector. The maximum size of a single partition that can be used by FAT32 is 2 TB (2048 GB), and the size of the cluster used by various partitions is also appropriate, it makes hard disk usage more efficient. The partition and cluster are merged as follows. We can make a careful comparison:
Partition size FAT16 cluster size FAT32 cluster size
16 MB-32 MB 2 kb Not Supported
32 MB-127 MB 2 kb 512 bytes
128 MB-255 MB 4 kb 512 bytes
256 MB-259 MB 8 KB 512 bytes
260 MB-511 MB 8 KB 4 kb
512 MB-1023 MB 16 KB 4 kb
1024 MB-2047 MB 32KB 4KB
4 kb Not Supported for 2048 MB-8 GB
8 GB-16 GB does not support 8 KB
16 GB-32 GB does not support 16 KB
32 kb or above is not supported
With the support of the current hardware, for example, dividing an 8 GB hard disk into a single partition, the size of the cluster used is only 4 kb, which saves a lot of space compared with the previous FAT16.
Iii. Restrictions on FAT32 usage
With these advantages, you can't wait to convert FAT16 to FAT32. However, pay attention to the following points before conversion:
(1) incompatible with other PC operating systems. Currently only MS-DOS 7.10, ROM-DOS 7.10, FreeDOS, and Windows 2000 and later versions are supported for FAT32, while other operating systems cannot read partitions for FAT32 at all. For example, you to MS-DOS 6. x and other old versions of the DOS boot disk boot, your hard disk FAT32 partition will disappear out of thin air, can not see this partition. In addition, if you want to use multiple boot times to start a variety of different operating systems, we recommend that you do not change the C: partition to FAT32. Some Operating Systems force you to install and boot from the main partition C:. If you change C: To FAT32, the operating system does not recognize FAT32, you cannot start the instance.
(2) Some disk tools and anti-virus software do not recognize FAT32, which may cause disk processing for FAT32 partitions after conversion, anti-virus software does not recognize such a file system and misjudges it as a virus.
(3) Some older versions of software cannot be executed in FAT32 partitions, such as Office 95.
(4) Partitions smaller than MB are generally not converted to FAT32. Although we found from the previous list that the partitions smaller than MB only use clusters of bytes size, but in Windows 98, you can only convert the partitions above MB. To convert a partition of 32 MB to MB, you must use the/MIN command in CVT. EXE, such as cvt d:/CVT32/MIN or FDISK/FPRMT.
(5) do not compress the disk in the FAT32 partition, even if the disk in Windows 98 is compressed.
(6) If your motherboard BIOS supports the "suspend-to-disk" function, disable this function because it is not available in the FAT32 partition.
(7) The conversion tool provided by Windows 98 can only convert FAT16 to FAT32, and cannot switch from FAT32 to FAT16. To be converted back, only Partition and Format are re-installed, and the system and application software are re-installed.
To switch from FAT32 to FAT16, you can also use the PowerQuest Partition Magic 3.0 or later. This is a set of software that allows you to freely change the partition size and file system without damaging disk data. You can use this software to convert FAT32 to FAT16 without reformatting your beloved hard disk. If you do not have this software, you must have the idea of "Preparing for regret". Please back up before FAT16 converts FAT32. At the same time, we remind you that if your computer configuration is not very high (that is, it is not P Ⅱ or the same level of CPU), it is best not to convert the partition table to FAT32, this will affect the hard disk reading speed.