I have a Dell Precision M90 with Windows XP and Windows 7 on it, and they're both x86. I'm considering upgrading my Windows 7 to x64 because the Core2 Duo T7600 has a 64-bit architecture, but I don't know if I want to upgrade to Windows XP Pro x64 because the WEPOS registry hack doesn't work on it, it seems like it was less supported during its lifetime than x86 XP, and I don't know how easy it'd be to get a Windows XP x64 product key nowadays. My machine only supports a maximum of 4gb of RAM, so would it be worth it to upgrade Windows 7 and XP to the x64 variants? Thanks...