AMD to design new micro-architecture for 2015 launch under chip guru Jim Keller

K7 and K8 lead developer Jim Keller to return to AMD to work on new micro-architecture design

AMD is planning to launch a new x86 micro-architecture before the end of next year in a development led by Jim Keller, the lead developer behind the K7 and K8 AMD micro-architectures.

Keller left AMD to join start-up PA Semi as its vice president of engineering in 2004, before shifting to Apple when it acquired PA Semi in 2008. PA Semi designed ARM-based microprocessors and was acquired by Apple to work on the A-series of microprocessors that today power iPod, iPad and iPhone Apple products.

Keller returned to AMD in August 2012 and has since worked on the company's emerging ARM design strategy.

The aim of the AMD micro-architecture overhaul is to overcome some of the efficiency shortcomings that AMD has run into in its current-generation Bulldozer micro-architecture.

Bulldozer was developed from scratch. It adopted a clustered multi-thread design last seen in the Digital Alpha 21264 Risc microprocessor.

Each microprocessor runs dual-core modules enabling the processor-series to scale up relatively easily. However, the drawbacks in the design have so far outweighed the advantages.

"Each dual-core module is alike a dual-core processor when it comes to integer power, and to a single-core processor with simultaneous multi-threading capability in its floating-point performance (each module has two arithmetic logic units, yet, essentially, one floating point unit). Since each module shares certain resources between two 'cores', in many cases their efficiency is not high enough," claims specialist microprocessor website XbitLabs.

The performance shortcomings of Bulldozer has put AMD at a disadvantage to its main rival Intel. "As a consequence, in many cases AMD's eight-core FX-series central processing units are behind in terms of real world performance when compared to Intel's quad-core chips that have the same number of floating point units (FPUs) which are more efficient compared to AMD's FPUs," claims XbitLabs.

However, with chip guru Keller now back leading x86 core design, the company is planning an all-new micro-architecture to bridge the performance gap. According to reports, the clustered multi-thread design will be ditched in favour of a design incorporating simultaneous multi-threading capability - like Intel's Hyper Threading technology.

Details of the new micro-architecture will be unveiled during 2015, with parts expected to appear in 2016. Bulldozer will make its final appearance in the form of the Excavator cores that will appear in the 2014 accelerated processing units code-named Carrizo and Toronto.