Open "My computer", then right-click the hard disk icon that you want to format. Click "Format". In the opened window, select file system and set the cluster size to be used by this disk.
If you are running Windows 7 or Windows XP with the NTFS file system choosing the size of the cluster vary between 512 bytes and 64 kilobytes. If you are using the FAT file system, then there is no choice, only one option is available to 64 kilobytes. As FAT32 you can choose the amount between 1024 bytes and 32 kilobytes. The widest range of cluster sizes is supported by the file system exFAT – from 512 bytes to 32 Mbytes.
Determine which use a cluster size when formatting hard drive. It will depend on the files that will be stored on a flash drive or hard drive. If it will be a small file size, select a smaller cluster size. If the drive is designed for storing video, music, and other files of great volume, would be the optimal choice of the larger size of the cluster.
Please note when selecting the size of the cluster is the fact that it represents the minimum amount of space allocated on disk. For example, if the chosen cluster size of 512 bytes, and the file copied to it, weighs 1 byte, it will occupy to store all 512 bytes. Therefore, a large number of small files takes up less space on the disc, where the cluster size is smaller. From another point of view, the larger the cluster, the faster will be the operation of recording and reading information. For the disk on which you are going to copy only movies select the maximum cluster size, and flash, designed to work with documents, install the minimum size.