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Article ID: 143148 - Last Review: November 1, 2006 - Revision: 4.1

This article was previously published under Q143148


When you create a primary, extended or logical drive partitions using Windows NT Disk Administrator, the following partition information appears:

   Minimum size for the partition is     X MB

   Maximum size for the partition is     Y MB   (Y=size of free space)

   Create partition size                 Z MB

where X is the minimum size for the partition. Y is the size of available free space and Z is the partition size you want to create.


The minimum size for the partition varies among different hard disks and hard disk controllers. Every partition must end on a cylinder boundary and the minimum number of cylinders is one. Depending on the capacity of the drive, geometry of the drive and the way the controller translates the drive determines the minimum size for the partition.

The following is an example that calculates the minimum partition size:

 DRIVE     translated geometry   bytes/sector          Equals
Capacity   #heads  X  #sectors      X 512        Minimum Partition size
--------   ------     --------   ------------    -----------------------

1GB         63     X    32          X 512     =  1,032,192 bytes  (1 MB)
2GB         63     X    64          X 512     =  2,064,384 bytes  (2 MB)
4GB        255     X    64          X 512     =  8,355,840 bytes  (8 MB)

  • Microsoft Windows NT Workstation 3.5
  • Microsoft Windows NT Workstation 3.51
  • Microsoft Windows NT Server 3.5
  • Microsoft Windows NT Server 3.51
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