about 64 bit XP PRO

[sydetys]

Hi!

I thought to buy Windows XP PRO.....64 bit version and dual boot with 64 bit vista.

Now, I know 64 bit vista works as well as 32 bit....and even better, and compatibility is at the same level

only one old game refused to run...I don´t know if it runs with 32 bit vista but anyway

Is this wise? Is Windows XP PRO 64 bit version as good as 32 bit? compatiblity with 32 bit older programs/games?

or was 64 bit XP crappy if copared 32 bit?

My main worry is compatibility, all games (older) are 32 bit and runs good with normal XP...but is 64 bit XP as good to run 32 bit programs as vista x64?

I trust you got it, so I stop repeating myself.

thanx

[MANEMAN]

Compatibility with 32-bit applications

Windows XP Professional x64 Edition uses a technology named Windows-on-Windows 64-bit (WOW64), which permits the execution of 32-bit x86 applications. It was first employed in Windows XP 64-bit Edition (for the Itanium), but then reused for the “x64 Editions” of Windows XP and Windows Server 2003.

Since the X86-64 architecture includes hardware-level support for 32-bit instructions, WOW64 simply switches the process between 32- and 64-bit modes. As a result, X86-64 architecture microprocessors suffer no performance loss when executing 32-bit Windows applications. On the Itanium architecture, WOW64 was required to translate 32-bit x86 instructions into their 64-bit Itanium equivalents—which in some cases were implemented in quite different ways—so that the processor could execute them. All 32-bit processes are shown with *32 in the task manager, while 64-bit processes have no extra text present.

Although 32-bit applications can be run transparently, the mixing of the two types of code within the same process is not allowed. A 64-bit application cannot link against a 32-bit library (DLL) and similarly a 32-bit application cannot link against a 64-bit library. This may lead to the need for library developers to provide both 32- and 64-bit binary versions of their libraries. Windows XP x64 Edition includes both 32- and 64-bit versions of Internet Explorer 6, in order to allow for the possibility that some third-party browser plugins or ActiveX controls may not yet be available in 64-bit versions.

Older 32-bit drivers and services are not supported by 64-bit Windows, but video and audio codecs such as XviD or OggDS (which are in fact 32-bit DLLs), are supported as long as the media player that uses them is 32-bit as well.