NTLDR Missing giving me a fit

[turbines]

I bought a used 600X with no operating system installed. The first time I tried to boot to the XP install disk I got a "NTLDR missing - Press CTRL>ALT>DEL to restart". I then updated the BIOS and still got the same result. I replaced the 12 GB hard drive with a new 40 GB and still got the same result. I then removed the hard drive from another 600X that has XP installed on it and put that drive in the problem machine. The machine boots to Windows with no errors using that drive.

The boot device configration is set to boot from the CD-ROM first, floppy second and HDD last.

Help Please!