Windows XP 64-bit Edition

From Wikipedia, the free encyclopedia

Windows XP 64-bit Edition

Website:	Windows XP
Company/ developer:	Microsoft
OS family:	Windows NT
Source model:	Closed source
Latest stable release:	2003 / March 28, 2003
Update method:	Windows Update
Kernel type:	Hybrid kernel
Default user interface:	Graphical user interface
License:	Microsoft EULA
Working state:	Unsupported

Microsoft Windows XP 64-bit Edition was a version of Microsoft's Windows XP operating system designed to run on Intel Itanium family of microprocessors in their native IA-64 mode. It should not be confused with Windows XP Professional x64 Edition, which is designed for x86-64 processors.

Two major versions of Windows 64-bit Edition were released:

• Windows XP 64-bit Edition for Itanium systems, Version 2002 — Based on Windows XP codebase, which was released in 2001
• Windows XP 64-bit Edition, Version 2003 — Based on Windows Server 2003 codebase, which added support for the Itanium 2 processor, was released on March 28, 2003. [1]

Windows XP 64-bit didn't fall into one of Microsoft's then current Windows XP product lines ('Home', 'Professional', 'Media Center' or 'Tablet') but was a separate edition made solely for the Itanium processor and its 64-bit instructions. However it was mostly analogous to Windows XP Professional Edition, but with some limitations:

• Initially it lacked most media applications such as Windows Media Player, NetMeeting, Windows Movie Maker, and integrated CD burning, although WMP and NetMeeting were added in the 2003 version.
• Numerous old technologies such as DAO, Jet database and most notably NTVDM were removed, so support for MS-DOS, POSIX, OS/2, and Win16 applications is absent.

However, unlike previous alternate architecture ports of Windows (Windows NT 4.0 for PowerPC, MIPS R4x00, and Alpha) Windows XP 64-bit Edition could run standard x86 32-bit applications through its WOW64 (Windows on Windows) emulation layer. While the original Itanium processor contained an on-chip IA-32 decoder, it was deemed far too slow for serious use (Running at about 400MHz), so Microsoft and Intel wrote a software 32 to 64 bit translator dubbed the IA-32 Execution Layer. It allowed real time translation of x86 32-bit instructions into IA-64 instructions, allowing legacy 32-bit applications to run (albeit significantly more slowly than native code).

[edit] Criticism

Windows XP 64-bit Edition could not use 32-bit drivers and services (except for codecs such as XviD, which were actually 32-bit DLLs so they could be used if media players are 32-bit). Thus, many (older) devices are incompatible with this version of Windows.

Security updates were discontinued for Windows XP 64-bit Edition because of the more recent release Windows XP Professional x64 Edition. Many fans of old DOS games have been reluctant to install 64-bit edition since the 64-bit edition lacks support for DOS applications.

[edit] External links

• Microsoft - 'Microsoft Windows XP 64-Bit Edition'
• WinSuperSite - 'Introducing Windows 64-bit Editions'