In order to be eligible to receive Windows® XP Professional x64 Edition, your computer must have been ordered between March 31, 2003 and July 31, 2005 with Microsoft Windows® XP Pro (32 Bit) preinstalled.So installing the 64-bit version of the OS will, technically, require one to remove the 32-bit version. There's a fair amount of wisdom in the practice of running parallel OS installs when dealing with a brand-new OS with iffy driver support, so the restriction is unfortunate.
In addition, you must read and agree to the following:
- By participating in this program, your 32-bit version of Windows® XP Professional will no longer be licensed.
- The installation of Windows® XP Professional x64 Edition requires you to format your hard drive. You must back up your files and settings prior to the installation or they will be erased. Microsoft is not liable for any loss of data as a result of this installation.
- Windows® XP Professional x64 Edition requires 64-bit hardware drivers (32-bit drivers are not supported). Drivers for 64-bit Windows are created at the discretion of hardware manufacturers and may not be available for some of your hardware components.
- For the purposes of the End User License Agreement for your existing Windows® XP Pro (32 Bit) software, your installation of this software will be an "Upgrade."
- The installation of Windows® XP Professional x64 Editions will void any support with your PC manufacturer. One free support call will be provided by Microsoft for any installation-related issues. Additional calls to Microsoft support will be available on a pay-per-incident basis.
- Cost for shipping and handling of upgrade is $12.00 USD for domestic shipments and $22.00 USD for International shipments plus any applicable taxes.
For those who bought pre-built systems with WinXP 32-bit installed, Microsoft appears to want you to go through your PC's manufacturer in order to get the upgrade. However, this page at least suggests MS will also upgrade copies of the OS not purchased with a PC:
The Windows XP Professional x64 Edition Technology Advancement Program enables customers who have purchased Windows XP Professional (32-bit) to exchange it for Windows XP Professional x64 Edition. You will need to have an x64 processor (the AMD Athlon 64, AMD Opteron, Intel Pentium 4 with EM64T, or Intel Xeon with EM64T) to run the new software.We are trying to confirm for certain whether home builders will be able to upgrade via this program.
I'm unsure whether it's the right time to make the move 100% to WinXP x64 Edition. I'm personally attempting that move right now on a new PC I'm building for myself, and the verdict is still out on whether or not it will all work right. My trusty M-Audio Revolution 7.1 sound card has no 64-bit drivers, and VIA's Hyperion 64-bit drivers for SATA and audio simply don't install correctly without a registry hack. In the case of the SATA drivers, that means the OS can't be installed directly on to an SATA drive.
That said, if you have the right hardware, WinXP x64 works well. You can read more about 64-bit computing in my little article on the subject.