FAT 16 and 32 HELP

[nymph4]

I am running win xp pro and when I go to format my secondary hard drive I go into My Cpmuter and right click on my secondary hard drive.

Then I left click on format and the format window comes up and I know I can just go with the defalt settings but I have a Q/A anyway??

The one dropdown list says FAT 16 or 32 or NTFS I get this.
But the dropdown list that says File Alocation Size has a list of Cluster sizes.

I know that you pick the smallist Cluster Size because the smaller the Cluster Size the More Clusters you can fit on the hard drive.

And it starts with 512 Bytes and moves to a biger Cluster size and so on.
Would you not just pick the 512 Bytes  why do they have a whole list of bigger Cluster Sizes??

[DukeIcewalker]

Someone might want to verify this-- but isn't the default cluster size 512?

Picking the default may save you some trouble down the road... and FAT is generally for floppy disks.

[Dias de verano]

512 bytes is default sector size. A cluster is one or more sectors.

Default values that Windows NT/2000/XP uses for NTFS formatting:

      Drive size                   
   (logical volume)             Cluster size          Sectors
   ----------------------------------------------------------
     512 MB or less               512 bytes           1
     513 MB - 1,024 MB (1 GB)   1,024 bytes (1 KB)    2
   1,025 MB - 2,048 MB (2 GB)   2,048 bytes (2 KB)    4
   2,049 MB and larger          4,096 bytes (4 KB)    8

However, when you format the partition manually, you can specify cluster size 512 bytes, 1 KB, 2 KB, 4 KB, 8 KB, 16 KB, 32 KB, 64 KB in the format dialog box


Larger cluster sizes give better performance but means that if you have lots of small files you will waste disk space.

[Deerpark]

Btw unless you need the hard drive to be accessible by an an operating system that doesn't support NTFS, you should format the drive as NTFS, it is a lot better than FAT 32.

[dahlarbear]

I know that you pick the smallist Cluster Size because the smaller the Cluster Size the More Clusters you can fit on the hard drive.

And it starts with 512 Bytes and moves to a biger Cluster size and so on.
Would you not just pick the 512 Bytes  why do they have a whole list of bigger Cluster Sizes??

No, you would not "just pick the 512 Bytes".  Each file system has a maximum number of clusters it can support.  Selecting 512 bytes would limit you to relatively small disk "volumes" since the supported volume size is "max_nbr_clusters times cluster_size".

From the following link:  Working with File Systems

Cluster Size

A cluster (or allocation unit) is the smallest amount of disk space that can be allocated to hold a file. All file systems used by Windows XP Professional organize hard disks based on cluster size, which is determined by the number of sectors that the cluster contains. For example, on a disk that uses 512-byte sectors, a 512-byte cluster contains one sector, whereas a 4-KB cluster contains eight sectors.

FAT16, FAT32, and NTFS each use different cluster sizes depending on the size of the volume, and each file system has a maximum number of clusters it can support. The smaller the cluster size, the more efficiently a disk stores information because unused space within a cluster cannot be used by other files. And the more clusters that are supported, the larger the volumes you can create and format by using a particular file system.


    * Windows XP Professional formats FAT32 volumes up to 32 GB regardless of cluster size. To format volumes larger than 32 GB, you must use NTFS. However, Windows XP Professional can mount FAT32 volumes larger than 32 GB that were created by other operating systems.

In the Disk Management snap-in, you can specify a cluster size of up to 64 KB when you format a volume. If you use the format command to format a volume but do not specify a cluster size by using the /a:size parameter, the default values in Table 13-4 are used. To change the cluster size after the volume is formatted, you must reformat the volume.


Before you choose a cluster size other than the default, note the following important limitations:

    *  For Microsoft Windows NT, Windows 2000, Windows Server 2003, and Windows XP Professional, the cluster size of FAT16 volumes from 2 GB through 4 GB is 64 KB, which can create compatibility issues with some applications. For example, setup programs do not compute free space properly on a volume with 64-KB clusters and cannot run because of a perceived lack of free space. For this reason, you must use either NTFS or FAT32 to format volumes larger than 2 GB. The format command in Windows XP Professional displays a warning and asks for a confirmation before formatting a volume that has 64-KB clusters using FAT16.

    *  Windows XP Professional, like Windows NT 4.0 and Windows 2000, supports file compression. Because file compression is not supported on cluster sizes above 4 KB, the default NTFS cluster size for Windows XP Professional never exceeds 4 KB. For more information about NTFS compression, see “File Compression” later in this chapter.

To check the cluster size of an existing volume, use the chkdsk command or the fsutil fsinfo ntfsinfo command. For more information about using Chkdsk, see Chapter 28, “Troubleshooting Disks and File Systems.” For more information about using Fsutil, see Windows XP Professional Help.

[patio]

MS KB articles sometimes just sheer aggravate me for taking simple terms and complicating them.
Not to mention being innaccurate from time to time.