It's a problem with NTLDR, a specific component of windows, rather than the entire operating system. If it was a lose IDE cable, I doubt that it would come up with only one specific component, but still doesn't hurt to check. Something I found to do before you reinstall windows using the recovery console, found on the boot CD:
Once you are in the recovery console, type map, and then press ENTER. Note the drive letter that is assigned to the CD-ROM drive that contains the Windows XP CD-ROM. Type the following commands, pressing ENTER after you type each one:
copy c:\i386\ntldr c:\
copy c:\i386\ntdetect.com c:\
If you are prompted to overwrite the file, type y, and then press ENTER.
NOTE: In these commands, there is a space between the ntldr and c:\, and between ntdetect.com and c:\.
Type the following command, and then press ENTER:
A list similar to the following list appears:
multi(0)disk(0)rdisk(0)partition(1)\WINNT="Microsoft Windows 2000 Professional" /fastdetect
If you receive the following message, the Boot.ini file may be missing or damaged:
The system cannot find the file or directory specified.
If this is the case, you will have to create a new Boot.ini, which I will let you know how to do if you need to. Hope this helps (this is supposed to and does for many people, but I haven't tried it personally yet).