Legendary chip architect Jim Keller accuses AMD of abandoning his K12 ARM CPUs

Renowned chip architect Jim Keller said that his K12 ARM CPU project was canceled by AMD after he left the company. Keller was speaking at the Future of Compute conference organised by the Indian Institute of Science's Department of Computer Science and Automation. 

Keller is known for his work on AMD's K8, ARM-based K12, and Zen 1 architectures. He also worked on the development of Apple A4 and A5 CPUs.

During his speech, Keller explained that ARM and x86 CPU had a lot in common including the cache design and execution unit. The only difference between the two processor architectures was the decode unit, which is why Keller and his team decided to work on a new CPU, called the K12. 

AMD was expected to launch its first K12 CPU in 2016, however, it is believed to have taken a backseat after the success of Zen architecture. At that time, it was believed that with the K12 CPU, AMD was eyeing low-power client devices such as notebooks and tablets.

ARM-based chips are also gaining a lot of traction in servers. Nvidia's new Grace CPU for servers is built on ARM architecture. Grace uses a chipset design to combine two CPUs as one. Nvidia was earlier planning to acquire ARM, but after regulatory roadblocks, decided to abandon the deal and instead signed a 20-year license for ARM design. Apple has also been using ARM-based CPUs in its MacBook and Mac devices since 2020, after moving away from Intel’s x86 CPUs. 

Though AMD's current focus is on its Zen 4 CPUs for servers and PCs, it has not given up on ARM architecture. In September 2022, AMD chief financial officer Devinder Kumar said that there is an interest in ARM-based solutions among customers and the chip company is "ready to manufacture ARM chips if needed." Kumar was speaking at the Deutsche Bank Technology Conference. 

Keller is currently building a team in India to develop a specialised chip to run AI programs, according to a Times of India report, published in April. He has also worked at Intel for almost two years leading the company’s silicon engineering team.