Is x86 32 bit or 64 bit?
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
).
Windows Vista reports x86
for 32bit version and x86-64
for 64bit version.
it's a 32 Bit version of Windows