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 Athlon 64 processors, was the first to implement it. This was the first significant addition to the x86 architecture designed by a company other than Intel.

Who invented the 64-bit processor?

Intel has been the microprocessor industry's 800-pound gorilla from the beginning. The company began 64-bit development in 1991, and the first systems with its 64-bit Itanium CPUs shipped in 2001.

Are AMD CPUs 64-bit?

AMD64 is a 64-bit processor architecture that was developed by Advanced Micro Devices (AMD) to add 64-bit computing capabilities to the x86 architecture.