This is caused by:
- Computer is booting from a non-bootable source.
- Computer hard disk drive is not properly setup in BIOS.
- Corrupt NTLDR and/or NTDETECT.COM file.
- Misconfiguration with the boot.ini file.
- Attempting to upgrade from a Windows 95, 98, or ME computer that is using FAT32.
- New hard disk drive being added.
- Corrupt boot sector / master boot record.
- Seriously corrupted version of Windows 2000 or Windows XP.
- Loose or Faulty IDE/EIDE hard disk drive cable.
Is there anyway you can get a proper XP or vista CD/DVD and try booting from it? some of those boot cds, especially the ones you get with Dell are rubbish. I know if you get into the XP or Vista OS bootup disc you can delete, format and check out partitions correctly.
If you are missing a sata driver you will probably find it is on a vista DVD as that driver database has been vastly improved over XP's.