Find drive`s cluster size is in Windows XP

To find out what the cluster size is for a particular drive,

• Enter cmd in Windows XP`s Start => Run box. Enter cmd

• chkdsk c: to check the C: drive (or any other drive`s letter to check that drive). After the quick check has taken place, a message appears that provides information about the drive. 

Note: The number next to the bytes in each allocation unit line.

The bytes in each allocation unit is the drive`s cluster size in bytes.

• To obtain the cluster size in kilobytes (KB), divide the number by 1024.
  
  
• For example, if Chkdsk shows 4,096 bytes in each allocation unit, then the cluster size is 4 KB. (4,096 bytes / 1,024 bytes per KB = 4KB). If it shows 512 bytes, you`ll have to format the drive to get it to 4KB.

• If it`s the C: drive and Windows XP is installed on it, you`ll have to format the drive and reinstall Windows and all of your software applications.

• To do that you would boot the system from the Windows CD/DVD (the BIOS might have have to be set to use the CD/DVD drive as the first boot drive). Note that you are given the option reformat the drive during the Windows setup process.

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