Hello,
If you have the 32bits Windows XP you will need be able to use GPT drives.
Check this link for more info.
http://msdn.microsoft.com/en-us/library/windows/hardware/dn640535(v=vs.85).aspx#gpt_faq_xp32_boot
To use this drive in your Windows XP computer I recommend you format it as MBR and not GPT