Advantages of Windows XP Professional x64 Edition
It is evident that the announcement of Windows XP Professional x64 Edition may turn out a significant stimulus for the software market as well as for the processor market, because the support of x86-64 by the operating systems will certainly offer the users a list of indisputable advantages.
Microsoft Corporation singles out five major reasons why Windows XP Professional x64 Edition will be more preferable than any of the currently widely spread 32-bit Windows-type operating systems.
First of all, Windows XP Professional x64 Edition is a new operating system, which can work with 64-bit application, which improves notably the performance and data processing efficiency. This advanced efficiency is achieved due to the fact that 64-bit applications can work with larger general purpose registers, and the number of these registers has become twice as big, compared with what the classical x86 architecture provides.
Secondly, Windows XP Professional x64 Edition supports much larger memory capacities. Thus, the maximum amount of physical memory supported by this new operating system is 32GB. As far as the virtual memory is concerned, the new operating system can support up to 16 terabytes of virtual memory. This way, the applications for Windows XP Professional x64 Edition are capable of processing much larger packs of data in the RAM. As you probably know, the 32-bit Windows versions cannot address more than 4GB of memory and do not allow allocating more than 2GB of memory for a single process. Windows XP Professional x64 Edition will completely eliminate these limitations.
Thirdly, one of the indisputable advantages of Windows XP Professional x64 Edition is the ability of this system to work not only with the 64-bit applications, but also with the traditional 32-bit applications without any functionality limitations or performance drops. This is possible due to a special x86 Windows on Windows 64 (WOW64) emulator built into the OS.
Also, among the advantages of Windows XP Professional x64 Edition Microsoft mentions the support of up to 2 single- or dual-core x86-64 processors and a corresponding programming model the software developers are already familiar with.
It is important to understand that all major advantages of Windows XP Professional x64 Edition are not that much the achievements of the Microsoft software developers, but are determined by the hardware innovations implemented in the new AMD and Intel CPUs supporting 64-bit extensions. Among these remarkable innovations I should definitely mention the new processor mode (Long 64-bit Mode), providing the support of 16 64-bit registers and linear 64-bit addressing. The backward compatibility with 32-bit applications is ensured by a special Compatibility Mode. These particular processor work modes are exactly the work modes the new Windows XP Professional x64 Edition operating system can use efficiently.
Although 64-bit extensions implemented in AMD processors are called AMD64, and in Intel processors are called EM64T (Extended Memory 64 Technology), they are compatible on the software level. In other words, Windows XP Professional x64 Edition can work on Athlon 64 processors supporting AMD64, as well as on Intel Pentium 4 processors supporting EM64T. Note that all applications developed for this OS should have no trouble working on either platform.