Differences between x86, AMD64, x86-64 and x64



AMD64, or “x64,”,Is a 64 bit computer processor architecture.It isBased on the existing 32-bit x86 architecture, developed by AMD,

applicationAMD64Instruction setOur own products are Athlon(Velociraptor) 64、Athlon 64 FX、Athlon 64 X2、Turion(Turion ) 64、OpteronOpteron )、Sempron(Flashing Dragon)、PhenomPhenom )And the latest phenom II and Athlon II processors.


Amd ultra micro semiconductor company

American AMDsemiconductorThe company specializes incomputersignal communicationAnd the consumer electronics industry design and manufacture a variety of innovative productsmicroprocessorCPUGPUAPUMotherboard chipsetTV card chipEtc.) and provideFlash MemoryAnd low power processor solutions, the company was founded in 1969.

Abbr. Advanced Micro Devices

Semiconductor (LED)

Intel [1]YesU.S.AA company to developCPUProcessor based company, is the world’s largest individualcomputerParts andCPUThe manufacturer, founded in 1968, has a 51 year history of product innovation and market leadership.

 IntelItanium processorBuilt on IA-64 (Intel Architecture 64), which means “IA-64 is a break with X86 code, it’s designed for the future.”.






Differences between x86, AMD64, x86-64 and x64

X86 is an instruction set. It is the compatible instruction set of 8086286386 when there was a personal computer.


“x86-64”,Sometimes referred to as “x64”, is a kind of 64 bit microprocessor architecture and its corresponding instruction set, also known as “x64”It is an extension of Intel x86 architecture.

X86-64 “1999 designed by AMDAmd publishes 64 bit set for IA-32 for the first time, which is called x86-64 (later renamed AMD64). Later, it was adopted by Intel,Now Intel calls it Intel 64



AMD64 architecture adds 64 bit registers on IA-32, and is compatible with early 16 bit and 32-bit software, which makes it easy for existing X86 based compilers to convert to AMD64 version.

becauseAMD64 and intel64 are basically the same,Many software and hardware products use a term that does not tend to either side to indicate that they are compatible with both architectures at the same time. For this purpose, AMD’s original name for this CPU architecture – “x86-64” is used from time to time, as well as the variant “x86″_ 64”。 Other companies such as Microsoft and sun use “x64” as an abbreviation for “x86-64” in their marketing materials.

Many operating systems and products, especially those that introduced “x86-64” support before Intel entered this market,Use “AMD64” or “AMD64” to refer to both AMD64 and intel64.


Intel hasWe use our own 64 bit IA-64 technology on Itanium processor,Although Intel 64 is also 64 bit, they are not compatible,That is, IA-64 software cannot run directly on Intel 64.

X86-64 used by Intel 64 is an extension of IA-32 instruction set, while IA-64 is another independent architecture without any shadow of IA-32.

Although IA-64 can run the instructions of IA-32 through simulation, the instructions need to be converted before they can run on IA-64.

Since x86-64 is derived from IA-32, the performance of running IA-32 and 64 bit programs is more than enough.