AMD's top microprocessor architect Jim Keller has walked from the chip vendor, just months after the company unveiled a shift in strategy to reinvest in high-end FX CPUs.
Keller quit on Friday, having returned to AMD in 2012 after most recently working at Apple.
It's unclear why the industry veteran has walked away from the chipmaker. Keller had been leading AMD's Zen project.
The x86 cores were expected to be packed into AMD's FX chips, with an arrival date pinned for 2016.
During Keller's previous stretch at AMD, he helped to develop the company's 64-bit Athlon and Opteron designs.
He also coauthored the x86-64 processor instruction set, as well as working on several DEC Alpha designs.
Keller returned to AMD for three years armed with plenty of ARM knowledge, following his work at Apple.
An AMD spokesbeing told Bloomberg that his exit was "not expected to impact our public product or technology road maps.” ®