See:
http://wdc.custhelp.com/cgi-
bin/wdc.cfg/php/enduser/std_adp.php?
p_faqid=928&p_created=1049320914&p_sid=uohSBsch&p_lva=&p_sp
=cF9zcmNoPSZwX3NvcnRfYnk9JnBfZ3JpZHNvcnQ9JnBfcm93X2NudD02Nz
YmcF9wYWdlPTE*&p_li=
If the link doesn't work:
1. Go to
www.westerndigital.com
2. Go to Support, then Knowledge Base, then Freq. Asked
Questions
3. The answer is given in Topic #4, Answer ID #928.
Pasted here:
Problem
The full capacity of EIDE drives larger than 137GB (128GB
binary) is not recognized in Windows 2000/XP.
Resolution
48-bit LBA support is necessary for drives larger than
137GB (128GB binary). The following conditions are
necessary for the correct functioning of 48-bit LBA
support in Windows 2000/XP:
Windows XP Service Pack 1 (SP1) must be installed for
Windows XP versions prior to August 2002. For information
about SP1, see Microsoft Article 322389.
The system must have a 48-bit LBA-compatible Basic
Input/Output System (BIOS) installed. This includes EIDE
controller card BIOSs.
You must enable the support in the Windows registry.
The Microsoft Knowledge Base articles listed below provide
important information about 48-bit LBA support for drives
larger than 137GB in Windows. For full details, carefully
review the relevant article.
48-bit LBA Support for ATAPI Disk Drives in Windows 2000.
How to Enable 48-bit Logical Block Addressing Support for
ATAPI Disk Drives in Windows XP.
Note: The above articles reference making necessary
registry changes. It is strongly advised that you contact
Microsoft directly for assistance.