Is x86 32 bit or 64 bit?

I have a copy of Windows in MSDNAA and it says Windows Vista x86. Is this Windows Vista 32 bit, or 64 bit?

JFW

Posted 2010-09-09T11:20:10.333

Reputation: 2 094

Answers

In current terminology x86 normally indicates 32-bits, with x86-64 or x64 indicating 64-bits.

x86 really refers to an instruction set based on the Intel 8086 (from some time ago - 1973 by Wikipedia's reckoning). Nowadays this normally is taken to simply mean a 32-bit instruction set. Initally it was a set of instructions that operated with only 16-bit, so historically could be referred to as x86-16 or x86-32. But, obviously, x86-16 is no longer relevant as 16-bit processors died out a long time ago.

x86-64 (or just x64) is an extension to the x86 instruction set, providing support for 64-bit registers, memory space and the like. It is fully backwards compatible with the 32-bit x86 instruction set (allowing 32-bit software to be compatabile without modification in most cases) and is taken to simply mean a 64-bit instruction set.

There are vendor-specific names for x86-64 as well - it can be referred to AMD64 or Intel 64 (previous IA-32e and EM64T).

DMA57361

Posted 2010-09-09T11:20:10.333

Reputation: 17 581

Windows Vista reports x86 for 32bit version and x86-64 for 64bit version.

Andrejs Cainikovs

Posted 2010-09-09T11:20:10.333

Reputation: 2 611

it's a 32 Bit version of Windows

lajuette

Posted 2010-09-09T11:20:10.333

Reputation: 4 364

You have a 32 bit Version
x86 is for 32 bit only. It is sometimes also referred to as x86- 32 .
x86- 64 supports 64 bit. They often referred by the term x64

subanki

Posted 2010-09-09T11:20:10.333

Reputation: 6 702

1The last part of your answer doesn't make sense. x86 refers to 32-bit, so you can be sure. – MDMarra – 2010-09-09T11:28:37.850

I am sorry there was some editing mistake in my answer, hence it seemed to be a wrong answer – subanki – 2010-09-09T12:48:30.993