X64 Vs X86 Processor
The original specification, created by AMD and released in 2000, has been implemented by AMD, Intel and VIA . The AMD K8 microarchitecture , in the Opteron and Athlon64 processors, was the first to implement it. This was the first significant addition to the x86 architecture designed by a company other than Intel. Intel was forced to follow suit and introduced a modified NetBurst family which was software-compatible with AMD's specification. VIA Technologies introduced x86-64 in their VIA Isaiah architecture, with the VIA Nano .