Microsoft Windows XP X64 Edition is the first Windows XP that fully takes advantage of X86 based processors.
theres nothing really to review on this as its basically identical to the 32-bit Windows XP Professional. Except its based on Windows 2003 server and requires 64-bit capable processor. 64-bit XP Professional can support up to 128Gigabyte physical ram and 16 Terabyte Virtual RAM. (remember. windows xp x64 and windows xp 64-bit edtition are different. 64-bit edition windows xp is only for IA-64 Intel Itanium chip. X64 windows xp is for regular 64-bit supported processors like the AMD Athlon 64 line and Intel processors supporting EM64T)
Windows XP X64 built 3790 Service Pack 1.. If you have a 64-bit processor and dont have any need for special drivers (scanners, printers, expansion cards) you can feel free to download a evaluation copy from Microsoft’s website.
As you can see it is no different from 32-bit windows xp professional. (since this is anevaluation copy. you’ll notice the Windows XP Professional x64 Edition Evaluation copy. Build 3790 (Service Pack 1) ) notice on the bottom right hand corner of the image above the taskbar and clock.
it theoritically can support all 32-bit applications except for 32-bit anti-virus, firewall and drivers. As well as support for future 64-bit software.
overall. 64-bit XP is still as stable as 32-bit windows xp as its based on windows 2003 server but it doesnt have good support for legacy drivers (such as scanner, some if not most expansion cards, printers etc etc). Most big companies such as motherboard makers, ATI, nVidia, creative etc etc are starting to release improved 64-bit drivers for 64-bit operating system (XP Pro X64 and X64 Vista)