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I have an old laptop and I need to convert FAT32 partition to NTFS format. I've read two articles about formatting to NTFS and then about aligning partitions to 4kB boundaries (see links below). My questions are:

  1. is this an issue only with newer drives (Advanced Format option)?
  2. is this an issue when converting FAT32 to NTFS without AF option (old drives)?
  3. why is it not an issue (as the articles indicates) in newer systems like Windows 7 (what's the difference)?


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up vote 4 down vote accepted

The first link is saying that

  1. If the drive was formatted FAT32 before Windows XP (or maybe 2000)
  2. the clusters on the drive will (or may?) not be aligned on 4KB boundaries
  3. which is what NTFS actually wants
  4. and then the CONVERT utility will then create 512-byte clusters
  5. which are less efficient

So it suggests that you run a utility to make sure the clusters are aligned before you CONVERT.

The issue with new 4KB-sector drives is different. If you have 4KB clusters (which is likely) then if they are not aligned, that's bad in terms of I/O because you have to do two reads/writes for each cluster. But this earlier problem is that it won't CONVERT to 4KB clusters, which is bad for I/O because you have to do more reading/writing of smaller clusters.

The problem described at the first link is (1) not an issue only with newer AF drives; (2) is an issue converting from FAT32 with any drive; (3) might be fixed in Windows 7 if the CONVERT is smarter and more aggressive -- fixing the alignment requires more work.

If you can verify that the FAT32 clusters are already aligned, then it won't be an issue. But no easy, non-geek way of doing this with Windows comes immediately to mind....

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I was surprised that 4kB alignment issue wasn't mentioned in context of newer AF disks. Additionally it looks like I've omitted "except" word before "Windows XP". Anyway I'll check the alignment. Geek way is not a problem here ;) – qlf00n Apr 26 '11 at 21:33

The alignment to 4KB boundaries is only needed for the newer "large sector" drives that tend to be >2TB large, all old drives below 2TB use a standard 512-byte sector that has been used since hard drives were created and is supported by practically every operating system you can think to install.

The reason this is not an issue with Windows 7 and "new" operating systems is that they were built to be aware that 4KB sectors are a possibility and not to assume the "standard" 512byte sector and so, when creating partitions they will automatically align the partitions correctly.

For your conversion to NTFS the


command should suffice, though backups are always recommended, just to be safe. I've run that on a live system without problems but it pays to be cautious.

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That's not an issue for the file system but the underlying partition (which is the space on the hard disk reserved for the file systems). So you need a partitioning tool that can handle this.

For Windows XP, try the "Western Digital Advanced Format Software" It should do the right thing automatically (even for non-WD disks)

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