China's Hygon chips outed as Epyc in disguise

Details have begun to emerge regarding Dhyana, an x86 processor family produced for the Chinese market by local company Hygon, and the legal loopholes AMD has jumped through to provide the core intellectual property - and, if reports are to be believed, the central design itself.

That China is looking to bring more of its technology in-house is no secret: The nation's government has long been funding local semiconductor companies and other related technological endeavours, most recently by exempting Chinese chip companies from corporation tax for five years followed by payments at a reduced rate of 12.5 percent for a year thereafter.

Thus far, however, the country's native chips have been relatively underwhelming. China's most well-known family of processors, the Loongson 'Dragon Core' family, is based on the MIPS64 instruction set architecture, are produced on a 28nm lithographic node, and top out at a mid-table clock speed of 1.5GHz.

Hygon's Dhyana is different: Based on the AMD64, or x86-64, instruction set, Dhyana offers everything you might expect of a modern processor including many-core implementations, simultaneous multithreading, and 3GHz plus clockspeeds. The reason for the sudden jump in performance: They're AMD Epyc chips in disguise.

Tom's Hardware has published an analysis of how AMD has been able to, effectively, sub-license its x86 licence, and it's a complicated dance involving two companies: Haiguang Microelectronics Co. Ltd (HMC), which is majority owned by AMD, and Chengdu Haiguang Integrated Circuit Design Co. Ltd (Hygon), which is not. By shuffling the intellectual property and finished products between the two companies, Hygon is able to bring 'Chinese' processors to market which, developers who have been working on Linux support for the parts claim, are so close to being Epyc components that you need only change the vendor ID and product family codes.

For those who are wondering whether Hygon's deal with AMD means cheaper Epyc parts on the horizon, there's some bad news: In order to stay within the terms of AMD's x86 licence agreement, Hygon's chips can only be sold within China and will not be available for export.