convert C drive to FAT32 while installing XP

Microsoft Windows xp professional w/sp2
January 11, 2010 at 14:15:26
Specs: Microsoft Windows XP Professional, 2.401 GHz / 2047 MB
Installing XP SP2, saw option to convert to NTFS, decided to have a go. All works, but ...

... I had chosen my C drive, to be converted to NTFS. Problem now is, that I do not know how to get this drive back to FAT. The XP format tool can do it, but not on the C drive (because the OS is there), and I can boot to DOS (different versions), but all of them will not see this drive, since it is NTFS.

So, how do I solve this one ? Install the OS on the other drive (I have 2 physical disks), then format the master drive as FAT, and install OS on main drive again ?

Know that the other drive (the second one) is actually in use for data only (no OS), and contains a nearly full FAT filesystem.

Is there another way ?


See More: convert C drive to FAT32 while installing XP

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#1
January 11, 2010 at 14:23:51
You mean fat32 not fat since your partitions have to be larger then 2gig which is fat's limit.

Your best bet, without third party utilities like Partiton magic, would be to backup what you want on c:, start the xp install via the bios, format the partition as fat32 [if 32gig or less otherwise you can't do it with xp] and then finish the xp install.

You will need your bootsect files if booting into dos.

You can't install xp on d: and then expect to format c:. C: is the boot drive. In MSspeak its the system drive and d: would be the boot drive if you installed the os on d:. You would once again face the issue of not being able to format c: because the OS would not allow you to.


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#2
January 11, 2010 at 14:27:26
Yes, it's FAT32 ... I mean FAT32 when I say FAT, cause I assume that FAT is ancient, by now. Question is HOW do I format to FAT32 whilst installing XP ... there's only options to format NTFS, quick or normal.

Well, the question may be irrelevant, as XP seems pretty useless with FAT (unlike W98). And I'll not be able to access any drive, when floppy-booting to DOS, but I guess XP is superior anyway, so no need I guess.


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#3
January 11, 2010 at 15:37:36
You can boot up on a win98/ME disk containing fdisk and format.
I would start with fdisk and remove c:
Then with fdisk recreate c:
Mark the partition as active. Exit. Restart

Then I would do the following command
a:>format c: /s

This will format c: as fat32.

When you go to install xp you will have the choice of leave the file system as is. You of course will leave it at fat32 since you don't want to do all of this again.

Remember to backup what you need before you fdisk.


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Related Solutions

#4
January 11, 2010 at 15:54:05
XP can be installed on either NTFS or FAT32 partitions. But Microsoft deliberately capped the XP/FAT32 formating tool at 32GB to force you to use NTFS on larger partitions. If you want to install XP on a FAT32 partition larger than 32GB, you'd have to format using a 3rd party program prior to the XP installation.

The biggest disadvantages of FAT32 are the file size limitiation (4GB - 1 byte) & the larger cluster sizes (which result in increased slack space).

NTFS has a default fixed cluster size of 4k. The FAT32 cluster size varies depending on the size of the partition but it maxes out at 32k. What that means is, if you have a 1k file on an NTFS partition, it will occupy 4k of space with 3k of that space wasted (slack). But if you have the same file on a FAT32 partition with 32k cluster size, 31k is wasted.


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#5
January 12, 2010 at 03:34:48
I know about the cluster sizes, I have a different thead for that. It's a useless debate, since both NTFS and FAT32 allow a series of cluster sizes, and both have got a default, which is more suited for saving storage, than aimed at speed. In other words, the default cluster sizes are too small, whether NTFS or FAT32.

The cluster-debate is not related to the filesystem choice. Either one may max. out at 32K, but it's not relevant since nobody bothers to go higher than 4K already. You say yourself, you loose 3K for a 1K file already.

The default cluster size for FAT32 is 4K, not 32K, I think.

I also know that XP can be installed on a FAT32, that's what I had. I did a couple of runs of the installation, and on one of them, I choose the "convert to NTFS" option ... THAT is the problem.

I'm not saying that I need to have FAT32 on that drive now, but I was wondering that IF I want to, how to do that. It appears that MS made it as hard as possible, so you cannot do that. Actually, they did a pretty good job there.

And why would you want FAT32 ?
Well, there is a claim for better performance using FAT32, but only under specific (non-realistic ?) situations. But, there's also a better compatibility with both DOS and Linux. There is a reason why FAT32 is still used a lot. NTFS is not unconditionally better than FAT32, it is just not. Major drawback of FAT32 is file size limit, and also disk size limit (32G). Have a question there, cause I have 2 disks of 80Gig, using FAT32, default cluster size (I think), using all of those 80G if needed. One of those disks contained XP (now it is an NTFS disk however, but that is only after the second or third install). First install was with FAT32 disk, no problem seen.


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#6
January 12, 2010 at 03:40:50
> You can boot up on a win98/ME disk containing fdisk
> and format.
> would start with fdisk and remove c:
> Then with fdisk recreate c:
> Mark the partition as active. Exit. Restart
>
> Then I would do the following command
> a:>format c: /s
>
> This will format c: as fat32.
>
> When you go to install xp you will have the choice of
> leave the file system as is. You of course will leave it at
> fat32 since you don't want to do all of this again.
>
> Remember to backup what you need before you fdisk.
>

I'll try that. From what I understand, is that I also need to have a format tool from pre-XP, so that I can format 32+G harddisks ?!


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#7
January 12, 2010 at 06:47:19
98/me startup disk has both fdisk and format. You need fdisk to remove the ntfs system and format to format larger then 32gig. You can also use third party tools like partition magic

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#8
January 12, 2010 at 07:50:46
"the default cluster sizes are too small, whether NTFS or FAT32".

How do you figure FAT32 partitions are too small? Below are the default cluster sizes for Both. FAT32 when used with 32GB or larger partitions creates large cluster sizes. Using third party tools to make FAT32 partitions using non standard cluster sizes means that the integrated disk tools in Windows won't work on that partition.

Microsoft has seen fit to use 4k cluster size as the default in NTFS. I think they did lots of research before making that the default. That said, if you feel a larger cluster size will serve your needs better than you have the option using MSoft tools to use a different number without worries that built in disk tools will work or not.

For most users NTFS is better.

Cluster sizes

for FAT32 are as follows:
512MB to 8,191MB = 4KB
8,192MB to 16,383MB = 8KB
16,384MB to 32,767MB = 16KB
Larger than 32,768MB = 32KB

NTFS - All partitions on a PC = 4KB default


.


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#9
January 12, 2010 at 08:01:06
I would partly agree with that ... but I'm not an average Windows user. I would like to do some tests with non-default cluster sizes ... Maybe that is the reason why FAT32 can claim a better performance (on a low used disk) : bigger cluster sizes. (This means : LESS clusters)

Anyway, NTFS's default cluster size is also dependant on the disk size, it gets bigger than 4K when reaching 16TB ...

I know. Some day.


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#10
January 12, 2010 at 08:02:45
> 98/me startup disk has both fdisk and format. You need
> fdisk to remove the ntfs system and format to format
> larger then 32gig. You can also use third party tools
> like partition magic
>

It sort of worked : got rid of NTFS, but I can't decently format the disk now, the w95 and w98 formats do not allow my 80 gig to be used.


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#11
January 12, 2010 at 08:14:58
You need the updated version of fdisk.

http://support.microsoft.com/kb/263044


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#12
January 12, 2010 at 12:16:06
Well, that seems to be the solution indeed. I was planning to do that, but I've got it running in the mean time. I didn't have an FDISK on my Windows98 boot-disk (so also not the "updated" version) ... but I had one on my Windows95 boot-disk.

I used that FDISK, to remove the NTFS drive/partition (nicely mentioned as NTFS by the way). Then I set the Primary DOS partition (or whatever it was called) to that drive, and that option set the drive/partition as active as well.

So, I got rid of NTFS, with a formatted drive, but not formatted in a correct manner.

I used the FORMAT of my Windows98 disk, to get that right. But, instead of using "format C: /S", I had to use "format C:". There's some problem with memory management, allowing you to run without "/S", but not with.

Although it is better to format with that option, it didn't seem to be any issue at all, since I have no Windows on that drive anyway, so why bother making it bootable ? You could use "SYS" to get the drive bootable.

I didn't bother, and inserted the XP installation CD, and it was nicely showing "FAT32, clustersize of 32K, 80G allocated"

Note that the "format C:" which I ran earlier, did NOT show the correct size, only until the end of the process.


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