Why can the partition only be 32 GB if it's formatted as FAT?

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There's no "32 GB" restriction on FAT volume size as far as I know;
I have seen some HDs that are FAT formatted and they're about 120 GB.

So why is it this way in Boot Camp?
 
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32GB is a FAT32 limitation - Windows won't format a FAT32 partition greater than 32Gb, it'll only use NTFS. If you have 120GB partitions, they're not FAT32.
 
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If you have 120GB partitions, they're not FAT32.

I must be imagining things then. XD

hdfat32.png

(note: Fine, so it's not 120 GB; that was my friend's computer, not mine.
But it's still more than 32 GB; you get the picture. =P )



Actually, with D3v1L80Y's links and a little bit of Wikipedia-ing, I got it.




Windows 2000 and Windows XP can read and write to FAT32 filesystems of any size, but the format program on these platforms can only create FAT32 filesystems up to 32 GiB. Third party utilities are available which can format larger FAT32 filesystems. Thompson and Thompson (2003) write[8] that “Bizarrely, Microsoft states that this behavior is by design.” A Microsoft knowledge base article[4] indeed confirms the limitation and the "by design" statement, but gives no rationale or explanation. However, a Microsoft TechNet article states that the 32 GiB limit was an arbitrary limit imposed because many tasks on a very large FAT32 filesystem become slow and inefficient.[9] Peter Norton's opinion[10] is that “Microsoft has intentionally crippled the FAT32 file system.”

from http://en.wikipedia.org/wiki/File_Allocation_Table



At some point you have to say, "Enough is enough." After considerable discussion, 32GB was decided upon as the arbitrary cutoff point. Windows 2000 and higher offer only NTFS when formatting larger drives. Note, however, that Windows 2000 and higher will use a FAT32 drive larger than 32GB; they simply won’t create one. (For a 32GB FAT32 drive, it takes 4 megabytes of disk I/O to compute the amount of free space.)

from http://www.microsoft.com/technet/technetmag/issues/2006/07/WindowsConfidential/



Sigh... maybe in 1995, this was understandable, but I think computers in 2007 would be able to handle HDs *gasp* larger than 32 GB just fine. That's a huge lack of foresight on the part of MS...
 
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I stand corrected. Going by how Windows behaves, the 32Gb limit is an effective one - it won't let you format over that size.
 
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You can use other operating systems to format a drive to much larger sizes using FAT32.

However it is possible that in order to use bootcamp, you'd need to reformat using Windows XP, which is limited to 32GB as mentioned above.
 
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What would worry me is that there's a 32Gb limit for a reason. While Microsoft will happily pull figures for limits out of their arses, it wouldn't surprise me if the reason was that something may go wrong with larger partitions under FAT32, which is after all a botch of the original FAT filesystem from ages ago.
 
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I think they added the limitation to force people to move to NTFS - a closed standard that only they could access...

It's only recently that people have been able to reverse-engineer write-to drivers for NTFS, so external harddrives and the likes that were formatted using windows xp are mostly closed-off for linux pcs and macs.
 
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I think they added the limitation to force people to move to NTFS - a closed standard that only they could access...

It's only recently that people have been able to reverse-engineer write-to drivers for NTFS, so external harddrives and the likes that were formatted using windows xp are mostly closed-off for linux pcs and macs.

Of course *slaps forehead* we're talking about Microsoft, aren't we? ;)
 

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