AMD64, also known as x86-64, x64, or EM64T and Intel 64 to Intel, is a 64-bit CPU architecture introduced by AMD, starting with their Opteron processors. All processors are also backwards-compatible with the x86 instruction set. AMD64 should not be confused with IA-64, an incompatible architecture from Intel in their Itanium processors.



Community content is available under CC-BY-SA unless otherwise noted.