James B. Keller (born 1958/1959) is an American microprocessor engineer best known for his work at AMD, Apple, and Tesla. He was the lead architect of the AMD K8 microarchitecture (including the original Athlon 64) and was involved in designing the Athlon (K7) and Apple A4/A5 processors. He was coauthor of the specifications for the x86-64 instruction set and HyperTransport interconnect.
