Testing a Chinese x86 CPU: A Deep Dive into Zen-based Hygon Dhyana Processors
by Dr. Ian Cutress & Wendell Wilson on February 27, 2020 9:00 AM ESTIn 2016, through a series of joint ventures and created companies, AMD licensed the design of its first generation Zen x86 processors to be sold into China. The goal of this was two-fold: China wanted a ‘home grown’ solution for high-performance x86 compute, and AMD at the time needed a cash injection. The outcome of this web of businesses was the Hygon Dhyana range of processors, which ranged from commercial to server use. Due to the Zen 1 design on which it was based, it has been assumed that the performance was in line with Ryzen 1000 and Naples EPYC, and no-one in the west has publicly tested the hardware. Thanks to a collaboration with our friend Wendell Wilson over at YouTube channel Level1Techs, we now have the first full review of the Hygon CPUs.
Let’s Start From The Beginning
There are two/three primary manufacturers of x86 processors: Intel, AMD, and Via/Centaur. Both Intel and AMD have been competing in the high performance compute space for multiple decades, and the reason there hasn’t been any other competitors is due to licensing. Due to patents surrounding the x86 architecture, Intel doesn’t want anyone else coming in and treading on its market share dominance, and to complicate matters, it is AMD’s version of 64-bit x86 that is currently being used by all involved. Intel and AMD are inextricably linked in this way. Meanwhile. Via/Centaur is along for the ride, with a very small market share mostly in Asia, and a lack of a leading edge high performance competitor.
For those who haven’t been following AMD, the company has been through a number of ups and downs. A significant down was during its Bulldozer CPU architecture years, where costs were high, performance wasn’t great, and Intel pulled ahead significantly in all areas: laptop, desktop, commercial, and enterprise. The design of Intel’s CPUs and its market dominance strategy, combined with the lack of a leading edge competitive product for AMD along with the purchase of graphics IP company ATI, nearly bankrupted AMD. Through the leadership of the former CEO, Rory Read, AMD became stable, and under the auspices of current CEO Dr. Lisa Su, the company put heavy investment back into its x86 CPU design. At one point, AMD’s debt was higher than its tangible assets, and the company had to even sell its headquarters and lease the buildings back from the new owners to find the funds to stay afloat.
Another element of this ‘staying alive’ tactic was the sublicensing of AMD’s x86 IP, which ultimately created the Hygon Dhyana x86 processors for China. Some people will quote this as being a keystone for AMD staying alive, however it is of a general consensus that this sublicensing ultimately secured AMD only around $200m (until the US entity list ban) out of the original $293m deal. At that time AMD was already making quick strides into the consumer market with its Ryzen 1000-series processors, which offered eight cores with modestly competitive performance while beating Intel on performance-per-dollar, giving AMD enough to reinvest in its key areas. The sublicensing ultimately provided AMD more of a safety net, depending on the success of the first generation Ryzen product portfolio.
AMD Does Due Diligence
Simply stating ‘AMD sublicensed the IP of one of its x86 designs’ sounds a bit farfetched on most days of the week. If either AMD or Intel believed that the opportunity to let others sell its CPU designs was profitable, how come it took until 2015/2016 to ever come to fruition? Part of this story covers that while there was clearly some money in it for AMD here, it didn’t fall foul of any Intel-AMD licensing agreements. And most importantly, it didn’t contravene any US laws regarding the export of high-performance computing intellectual property.
This last point is important. The US government gives every CPU that comes out of Intel, AMD, and others, a value based on its performance. This is some combination of FLOPs and power, and those that surpass a specific threshold are deemed too powerful to be sold in certain markets. This includes semi-custom processors, where AMD/Intel fiddle with the core count/frequency and provide off-roadmap parts.
AMD at the time made the following statement:
Starting in 2015, AMD diligently and proactively briefed the Department of Defense, the Department of Commerce and multiple other agencies within the U.S. Government before entering into the joint ventures. AMD received no objections whatsoever from any agency to the formation of the joint ventures or to the transfer of technology – technology which was of lower performance than other commercially available processors. In fact, prior to the formation of the joint ventures and the transfer of technology, the Department of Commerce notified AMD that the technology proposed was not restricted or otherwise prohibited from being transferred. Given this clear feedback, AMD moved ahead with the joint ventures.
AMD had contacted the DoD and DoC, as well as all others, and had been given the green light. The new microarchitecture was deemed of low enough performance to not hit any of the export bans. AMD was also given crystal clear confirmation that the ‘technology proposed was not restricted or otherwise prohibited from being transferred’, which is a rather stark statement. At this point it should be clear that AMD may have submitted a modified version of its IP to the relevant US departments, rather than the microarchitecture we saw in the Ryzen 1000-series. This is part of what this review is about.
Joint Venture in a Joint Venture
The end goal of all of this was to be able to provide China a version of AMD’s Zen 1 CPUs that could be called ‘Chinese’, rather than ‘American’. As has been the case of the last decade or more, China has wanted to rely less on American technology and intellectual property in order to become self-sufficient. The way in which AMD’s joint ventures worked for the Hygon Dhyana designs was built to essentially do that in a very roundabout way.
The name of the joint venture overseeing the operation is called THATIC, or Tianjin Haiguang Advanced Technology Investment Co. Ltd. This company is owned by AMD and a mix of Chinese companies, both public and private, including the Chinese Academy of Sciences, but is at least 51% owned by AMD.
Two companies were created in order to perform the web of steps required – these companies would be jointly owned between AMD and THATIC (note that AMD also owns part of THATIC). These companies are:
- HMC: Haiguang Microelectronics Co. Ltd.
- Hygon: Chengdu Haiguang Integrated Circuit Design Co. Ltd.
Of these companies,
- HMC is 51% owned by AMD and 49% by THATIC.
- Hygon is 30% owned by AMD, and 70% by THATIC.
These companies fulfill different roles in the chain. HMC works with AMD for design and GlobalFoundries for manufacturing, while Hygon works with HMC to add co-design elements and packaging, then selling the silicon to China.
Licensing Core IP is Different to Sub-Licensing x86
A lot of confusion was made when the creation of the THATIC joint venture happened. The big overriding question was if AMD had somehow licensed the full x86 (and x64) architectures to a Chinese company, allowing them to build fully capable custom x86 CPUs and push both Intel and AMD out of the market there. This is not the case with the joint venture.
What AMD did was license a single core design to HMC, along with an SoC layout. From this point on, AMD is officially ‘hands-off’, but AMD engineers and executives are involved at HMC, so technically they are still present. With these core designs and SoC layouts, HMC sent the floorplans, not the RTL, to Hygon for requested updates. Hygon submitted the updates to HMC, which were either approved or rejected by AMD’s engineers. HMC would integrate the changes, and then take orders from Hygon for manufacturing. With Hygon’s order, HMC went to GlobalFoundries with the design and ordered the silicon. HMC then sold the silicon to Hygon, which packages the CPU into various configurations and sells it into the Chinese market. It is also up to Hygon to help design motherboards for the new platform(s).
Broken down into steps:
- AMD licenses core design to HMC with suggested SoC layouts
- HMC provides floorplan to Hygon
- Hygon suggests changes to HMC
- AMD engineers at HMC approve/reject changes
- HMC offers final floorplan to Hygon, ready to take orders
- Hygon orders wafers / silicon die from HMC
- HMC approaches GlobalFoundries for manufacturing
- GlobalFoundries achieves particular frequency/yield on new design
- HMC sells completed silicon to Hygon
- Hygon performs packaging on the silicon in China
- Hygon sells completed CPUs into China
Because HMC is the one providing Hygon with the IP, the CPU can now be classified as ‘Chinese’, despite the underlying design coming from AMD.
When AMD announced the creation of THATIC, it spoke about sub-licensing its Zen core IP to the joint venture. It was described as a multi-year partnership, however it was confirmed at a trade show that AMD was only sub-licensing a single version of its IP, and that there were no plans to sub-license any others in the works.
At the time, it was assumed that AMD had sub-licensed the same version of its Zen core IP that had already been released as the Ryzen 1000-series processors and EPYC Naples processors. However as part of this review will show, it would appear that AMD made some performance changes to the design before it was given to the joint venture – specific instructions have a lower throughput than what we saw from the processors coming directly out of AMD.
Not only this, but in that list of steps, point (4) is most apt. Hygon requested specific changes for the Chinese market. Before everyone leaps to ‘creating backdoors for the Chinese government’, we know of several modifications that were made due to Linux kernel updates. In China different elliptic cryptographic algorithms are used compared to the west, and so the hardware accelerated functions for these were changed, and different microcode used in order to enable these. Part of this review is to try and discover if there are any other changes as well.
The final product out of this spider web of arrangements is the Hygon Dhyana x86 core, an ‘updated Zen core for China’, which Hygon packaged for both embedded, commercial, and enterprise systems. We saw at Computex 2018 that Chinese server vendor Sugon was involved in this project, with the company showcasing its servers built on 32-core Hygon CPUs. Users that follow online benchmark databases also saw submissions for 8-core commercial and embedded variants, likely to be used for government and education deployments.
We should point out that we asked AMD several times what differences were in the Hygon Dhyana designs compared to the original Zen 1 cores. With ‘AMD’ playing a limited role in all of this, we were simply told that if we could get hold of one, if we identified changes to the design in our testing, they might consider confirming or denying them. For as open as AMD has been with us about the Ryzen and EPYC processor families, it was a stark contrast when talking about Hygon.
The first Hygon CPUs went into the Chinese market in 2018, however they were almost impossible to source. The Hygon CPUs were never meant to be sold to the west, and the nature of the CPU and the companies dealing with it meant that none that we could identify were ever interested in sampling us.
In 2019, the US created an ‘entity list’ of Chinese companies what are deemed a potential security threat to the US market. As a result, any commercial interaction with these companies, with products or IP that were at least 25% created in the US, are restricted and forbidden. THATIC was one of the companies placed on the list, which means that AMD can no longer license any additional IP to the joint venture. THATIC still has access to the original IP it licensed however, and can continue to manage it (albeit without AMD’s assistance), however the ban also restricts HMC’s ability to order silicon from GlobalFoundries, making the whole process in limbo if not defunct.
A big thanks to Usman Pirzada’s great write up, from which much of this was based on, as well as Drew Prairie from AMD who has provided additional context to AMD’s arrangement.
Working with Wendell: Sourcing Hygon CPUs
For this review, we were able to test two systems remotely housed in the lab of Wendell Wilson, the charismatic host of the Level1Techs YouTube channel. We were both approached by sources asking if we wanted to purchase systems, which we gather were old engineering samples from a Hygon or Sugon subsidiary based in the US that was performing post-manufacturing analysis and performance testing. That subsidiary has now been dissolved, a knock-on effect of the entity list ban, and the engineering hardware within that company was (unbeknown to us) sold off. We were given the opportunity to borrow a couple of systems that fell out of the dissolution. Due to location, Wendell offered to house them, take some pictures and video, while we both did performance benchmarks. Linus’ team from the popular LinusTechTips channel were also invited to participate – you can see the video that was produced here.
Ultimately we ended up with two systems to test – one commercial ‘Hygon Dhyana’ and one enterprise ‘Hygon Dhyana Plus’.
The commercial system looks like a normal 8-core Ryzen 1000-series system, however it is actually a BGA design and is not upgradeable. In fact this seems to be an early engineering sample, as the CPU doesn’t even have a number associated with it. There’s also something interesting going on with the mounting points, which we’ll cover in due course.
The enterprise system is a dual 32-core Hygon 2U server. These CPUs state that they are the ‘7185’ models, which we know to be the highest core count that Hygon offered, and one of the highest performance 32-core parts as well. Putting two of them into a server looks very much like a 2P EPYC Naples design.
It should be noted that we did see a Hygon processor before at a trade show, and you may notice some Chinese writing at the bottom. Interestingly enough, we got the bottom right of the CPU translated. A literal translation is
'Using Cores to Calculate The Future'
However, the second character used in the slogan is a homonym, which could be translated as:
'Using Passion to Calculate The Future'
Over the next couple of pages we’ll examine the two systems in more detail, and then a look into the fundamental differences we found at a core and SoC level compared to the Ryzen 1000 and EPYC Naples processors we’ve already tested in years gone by.
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Lord of the Bored - Friday, February 28, 2020 - link
It is still pretty dang clear: AMD Zen core goes in, China Zen core comes out. I don't think anyone didn't realize what AMD was doing, particularly as they crippled the processor.The convoluted part-ownership scheme is because AMD can't sublicense their x86 license due to an ancient settlement with Intel. So they need to maintain >half ownership to keep Intel from suing them.
sing_electric - Friday, February 28, 2020 - link
I know people that review these deals. They are smart and they aren't naive. That doesn't make them infallible, of course, but they are competent and take their job seriously.It seems to me that you've got it backwards: This ownership structure was set up *specifically* to meet Chinese requirements for "made in China" certification (which the central government is really pushing pretty hard) while actually making as little in China as possible - even shipping dies to China for packaging.
Mikewind Dale - Thursday, February 27, 2020 - link
Also, even if AMD *did* give IP to China, it's AMD's IP to give. It's not stealing if the owner gives it away. And it's not a betrayal of the USA, since the USA is supposed to be a free-market country that protects individual rights and liberties. If anyone is betraying the USA, it's the US federal government, since the US federal government would be violating Americans' rights and liberties by prohibiting voluntary market transactions (such as exports).sonny73n - Friday, February 28, 2020 - link
“ Lisa Su committed treason by exporting high tech IP to an enemy country“I don’t understand why the US has so many sick psychopaths who see everyone as enemy. I wonder if they also see you as an enemy, do you think you would still be here spouting hate right now?
TheinsanegamerN - Friday, February 28, 2020 - link
The chinese see themselves as above all other cultures, and are not only extremely racist towards those who ar enot chinese, but also employ methods such as concentration camps and "reeducation" facilities against those of certian religious and ethic backgrounds.but sure, prattle on about how hateful the US is.
PeachNCream - Friday, February 28, 2020 - link
Don't assign the actions of the Chinese government to the people living in China in a broader sense. That is unfair to average people that are, just by nature of birth and physical location, part of the population you are giving the blanket title of racist. It's just as bad as calling everyone from Alabama a pickup truck owning, gun-brandishing redneck when we know quite well that there are reasonable, decent people living there that have to spend time contending with that label on a daily basis.yannigr2 - Friday, February 28, 2020 - link
Trying to find the wrongs to others, is just an excuse to hide your wrongs.Look, they (Chinese) are worst that us (Americans).
Don't expect much support with that kind of logic. The lesser evil is not good.
sonny73n - Saturday, February 29, 2020 - link
“ The chinese see themselves as above all other cultures, and are not only extremely racist towards those who ar enot chinese, ”The first letter of any national should be capital. You’re a disrespectful person.
China has thousands of years old culture. If I’m a Chinese, I would be proud of it. And there’s nothing wrong if they see themselves above other cultures because it’s the fact.
They might be racists but who isn’t? If you’re talking about extreme racist, you should talk about Americans.
“ employ methods such as concentration camps and "reeducation" facilities against those of certian religious and ethic backgrounds.”
The US don’t need re-education facilities. MSM have been feeding BS to you since the day you were born. And it seems you did very good gobbling down all the BS. Now you’re only spouting fouls since you’re incapable of having any critical thinking.
You’re trying to say that you like most of the psychopaths in the US aren’t hateful but your comment shows that you are. Accusation without proof is the worst form of hatred you can give. Or maybe you’re just too stupid and lazy to find out the truth. So it’s much easier to repeat what CNN says.
Lord of the Bored - Saturday, February 29, 2020 - link
Comrade sonny73n, you say "accusation without proof is the worst form of hatred" immediately after calling all americans psychopaths withut proof. You undermine your own argument, and the party expects better of you.s.yu - Sunday, March 1, 2020 - link
>And there’s nothing wrong if they see themselves above other cultures because it’s the fact.Wow, I can't imagine anybody other than a modern Red Guard(they're popping up here and there under Xi in case some people haven't noticed) saying this.
These people hail the Party's words as gospel, blatantly disregarding the massive rift between the Party's words and actions, made possible only by the sore lack of accountability, in turn an inevitability stemming from the authoritarian and dictatorial nature of the regime. One proof of this is that in China you almost never win a lawsuit against the government, and you literally never win a lawsuit that leads to reforms in legislation, regardless of how the government tramples over its own laws to infringe on your rights. "Legal order" in China largely exists as excuses to prosecute the insubordinate. There's even statistics on the citation of legal code during lawsuits in China, and a conclusion was that ~90% of clauses have almost never been cited in practice, because they're effectively inapplicable.
>If I’m a Chinese, I would be proud of it.
This isn't outright denying that he's Chinese though.¯\_(ツ)_/¯
March 1st is the first day of a new round of crackdowns on flow of information in China, just more excuses to frame you with.
https://translate.google.com/translate?hl=en&s...
Yesterday though I personally witnessed a new mindfuck trick of the Party before my own eyes: if you try to upload an image to Wechat chat groups, it will be OCR'ed simultaneously, and if for whatever reason that meets whatever censorship standard your image is determined to be "sensitive", then it will meet one of at least four fates:
1. Fake upload: You thought you uploaded it, Wechat tells you that it's successfully sent, yet nobody in the group but you could see it.
2. Repost ban: The long press option of repost would be removed from an image.
3. Fake repost: People in the group you uploaded to could see it, but if you repost it to another group(which does not require another upload), it becomes invisible to people in that second group.
4. This is the good one: Within the same chat group, an image uploaded is only visible to certain people, and hidden from others!!
I'd known the first two for quite a while, and discovered the last two yesterday, but the last one really throws a wrench into any serious discussion, especially regarding content that's wiped out from within the wall in the first place.
I'm 100% certain of what I saw because regarding the fake repost issue, I was able to upload, and successfully repost an image(screenshot of a banned article) with a heavy gaussian blur, but the original was only visible to the initial group. Regarding the last issue, a guy uploaded three images, while I only saw two, and he tried uploading the missing one again, but it was still invisible to me, but all three were visible to the uploader himself and another guy in the chat group, so it's no glitch, it's intentional.
I don't believe this was related to the March 1st regulations, it was most likely in place before that. The exact impact of this new legislation remains to be seen.