Document your suggestion. Since when can't XP use a 120Gb partition, regardless of how it was created?
Don't read into what I said. I did not say XP can not use a 120 GB. The user has a problem. I told him how to isolate the problem. Try again with smaller partition made by XP is among the the first in a series of tests to identify the problem.
Information need here is:
Was the thing working OK before the install? Which OS?
Did the BIOS recognize the HDD?
Why didn he use the WD tools?
Which version of XP? Retail? OEM?
Has the CD-ROM been tested?
How much memory?
There is a reason to believe that a try again with small XP created partition works. It is not really an XP issue.