|Okay, so the bios is seeing the full size of the drive. |
Is XP's Setup seeing the full size of the drive too?
If it isn't, if you do want to install XP (see my notes about multibooting XP and Vista, probably applies to Windows 7 too), you need to make yourself a bootable "slipstreamed" burned CD, preferably a CD-R for best drive compatibility, that has the contents of the SP3 updates integrated into the contents of your original CD, and if your mboard has SATA drive controllers, you might as well integrate the drivers for that into the disk contents while you're doing that, and use that CD to install XP rather than your own.
Instructions for how to do that are available on the web from many sources.
You use the same Product Key you use with your original CD.
Whatever space on the hard drive that is un-allocated after Setup has finished can be software partitioned and formatted in Disk Management.
If you make the first partition, or any partition, 32gb or smaller, you have the option (in 2000 and XP at least) of installing a FAT32 partition rather than an NTFS partition (2000 and up won't allow you to make a FAT32 partition larger than 32gb because of Microsoft defaults, but you can use FAT32 for partitions larger than 32gb if you partition the drive with third party software rather than with Windows).
Some of us prefer using FAT32 for the Windows partition rather than NTFS for XP because there are more free things you can use to fix what is wrong when something goes wrong with Windows than there are for when it's on a NTFS partition.
I'm not sure whether Vista and Windows 7 have the option of choosing FAT32 for 32gb partitions or smaller, but if the partition has already been made FAT32, Vista, and probably Windows 7, will accept that fine.
FAT32 uses 32kb for it's allocation units for all partitions exactly 32gb (32,768mb) or larger, several steps of smaller allocation units for partitions smaller than that depending on the size range. The NTFS in 2000 and up uses 4kb allocation units for all files whatever the size of the partition.
The smallest space a file can take up on a drive is one allocation unit. The space not used up by a file in an allocation unit cannot be used by anything else, and that portion is often called slack space - it's essentially wasted space.
If you have a lot of huge files on a partition, e.g. music, movies, other huge files, there's not much if any difference between the slack space percentage for a FAT32 or NTFS partition, but if you have mostly smaller files, using NTFS yields you a lesser slack space percentage.
- a single file cannot be larger than 4gb on a FAT32 partition.
- a very few programs are not optimized to use a FAT32 partition. e.g. the TV or video recording feature of Media Center in XP MCE whines about you choosing a FAT32 partition location if you make it's location for the recordings on one. (If you also have a NTFS partition, that's not a problem - make the location for the recordings on a NTFS partition.)
Most versions of Vista and Windows 7 have a newer version of Media Center built in.
I often make my FAT32 partitions a tiny bit smaller than 32gb so that all files in it are using 16kb allocation units rather than 32kb ones.
Setup and Disk Management show the size in mb, 1,024 mb per gb, so if you want to do that, specify a size slightly less than 32,768mb, say, 32,760 .
You DO NOT have to install everything on the C partition, or on whatever the Windows partition drive letter is if it's not C.
Most programs can be installed on other than C if you do not use the default choice or the default path (location on a drive's partition) for where it is installed - e.g. choose a Custom rather than an Express installation choice, or change only the drive letter at the beginning of the path line where it is to be installed - in that case, only a bit is installed on C, the rest of the program is installed on another partition. If you reload Windows, if the program is on another partition it will have to be installed again, but if you install it in the same place, all user data that is where the program is that was there before you re-installed Windows will probably still be there.
Program installation files, driver installation files, manuals for your system, or other similar things, can be on any partition.
Data that is not a program can be installed on any partition. E.g. Keep all music, movies, documents, or copies of them, on other than C, or whatever the XP Windows partition drive letter is if it's not C, so they are not deleted if you ever need to re-load Windows.