New Motherboard and CPU

I've just installed a new Abit NF-95 motherboard along with an AMD 64 X2 3800+ CPU and 1G of 400Ghz kingston memory. When booting, the sytem runs through the self-check successfully, but when it tries to load windows (XP) it hangs up with the message "NTLDR is missing". The bios seems to be detecting the hard drive ok, and when I replace the board, CPU etc with the old one (Pentium III), XP boots up ok, so the files and drive are not damaged. The landing zone is the same in the new bios as the old. Can anyone help.

Many thanks

Andy

Did you install Windows newly on this system?

Or is the Windows version from another system with different hardware?

If you didn't, then you would have to clear the old hardware drivers from this drive first and then you would normally be able to use the same OS installed.