Windows install (only had SP1) didn't use entire HD

XP SP1 only recognises drives up to 137 Gb as you have discovered and SP 2 is required for larger drives. In addition the BIOS must include 48 bit LBA - as this is a recent build that should be no problem.

You cannot increase the size of the primary partition, or any partition through Windows and will need to use third party partitioning software such as Partition Magic or Acronis Disk Director to do this.

If you go down this route it is wise to have a backup of your data - should maintain one in any case.

With SP2 is installed you should be able to create a partition in the unallocated space (not unpartitioned) using Disk Management.

Your other option is to wipe the drive and start over with your slipstreamed SP2 disk.

My take on this would be to have two partitions - one for the OS and the other for your data. If the OS fouls up that partition can be reformatted for a fresh install without affecting your data on the second partition.

 

Since Pete said otherwise, I had to check in How to enable 48-bit Logical Block Addressing support for ATAPI disk drives in Windows XP and it confirms that I remembered correctly. XP SP1 supports 48 bit LBA. It seems to me that the XP install CD was RTM (no 48 bit LBA support).

Christer

 

Backup (Start > Programs > Accessories > System Tools > Backup) is installed by default in XP Pro. It is included in Home, but not installed by default ......

http://www.theeldergeek.com/backup_for_xp_home_edition.htm

Can be used to backup data, etc and also to make a copy of the OS and installed programs through ASR XP (Pro only) - Automated System Recovery Note a floppy drive is required.

For data backup I would highly recommend SynchbackSE - I use it literally on a scheduled hourly basis to back up my data to another drive. There is a freeware version Synchback - a long time since I last used that so I can't outline the differences - may be on their website.

An alternative, arguably better, is to use a disk imaging program such as Acronis or Ghost - these create a mirror image of the drive -everything - OS, all installed programs, data - the lot.
The other connection in which you may have heard the term 'mirroring' used is in RAID (Random Array of Independent Disks) where two hard drives can be set up to mirror each other. In otherwords the contents of the drives are identical - if one fails there is a complete mirror on the other drive which is active.