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 ESTHygon be Bygon
Every processor made in the US has to be of a certain performance level in order to be deemed suitable for export. Companies have pages and pages of documents relating to the performance of their hardware as determined by the metrics that govern the laws in the USA. These metrics include raw processing power, measured in gigaflops (GFLOPs), adjusted peak performance (APP), and/or the composite theoretical performance (CTP). Depending on which territory you export to, one or more of these metrics may apply.
One way around this, if you cannot import the CPU, is to have a license to build it. But more than that, if you can adjust the license and have a custom input into the design, you can relabel the hardware as a homespun device and be somewhat within the realms of plausibility. This is how one of AMD’s core designs, with modifications, has made it into a ‘Chinese’ x86 CPU for the Chinese market. The big plus on the packaging isn’t so much that it avoids import issues, but the ‘中国’ label that comes attached. Then again, one assumes that the people using these CPUs don’t exactly have a choice in what they can buy.
We discovered that these processors have been changed from the Zen 1 design in a number of ways. To say they are carbon copies of the Zen 1 SoCs, which is what a lot of people have suspected, is not true – enough has changed in the design to say that these parts are rebalanced, mostly for worse performance than their Zen 1 counterparts. The integer performance is essentially identical, however the floating point performance has been reduced – common instructions having half the throughput, and random number generation has been adjusted to be both slow and produce lower quality random numbers. The cryptography engines have also been replaced, such that common AES instructions are no longer accelerated but others more specific to the Chinese security, such as SM2, SM3, and SM4, are now included. In our testing, despite the processors showing AVX/AVX2 support when probed, it appeared to be disabled. We suspect this to be more of a firmware bug than a limitation of the Hygon CPU.
The method by which AMD was able to get an edited version of its first generation Zen core design into a ‘Chinese’ designed x86 CPU is highly convoluted. By first creating a joint venture with other Chinese companies called THATIC, then by forming two companies called HMC and Hygon each owned in different amounts between AMD and THATIC, how each business was able to discuss and control parts of the IP was sculpted in order to keep the secret sauce still in AMD’s hands, but allow the Chinese side of the ventures to request modifications. Those requests have to then be approved, and then HMC commissions the chips from GlobalFoundries, while Hygon packages them and sells them to companies like Sugon. We go into detail on this in our overview back on the first page, but suffice to say trying to follow where all the pieces are is almost like playing a game of Risk blindfolded.
With AMD unwilling to discuss on the record any of the finer details of the arrangement or changes to the processors, when asked if they could disclose how the processors were changed, we were told ‘if you find anything out, we may confirm it’. The one time I was able to see a Hygon Dhyana processor was due to a miscommunication with one of the Hygon vendors at Computex, and the person who let me take pictures suddenly stopped communicating with me after the event (I presume to keep his job). It still took over a year from those discussions to get hold of the chips for testing, and only then we were able to obtain the chips due to the current US Entity List ban covering one of the joint venture companies. This essentially killed the project dead, and caused one of the US subsidiaries to be mothballed, allowing some parts to leak onto the market where they had once been meticulously controlled.
Overall these Hygon CPUs offered China an alternative to the Intel market, and arguably something faster than they might have been able to purchase through import restrictions. AMD made some money at a time it badly needed it, but with the success of its Zen 2 platform, I don’t foresee AMD needing to do something similar over the next decade. The nature of the agreement between AMD, its joint venture THATIC, and the joint companies, was only for a single core design, Zen 1, and not Zen 2, limiting its competitiveness. Moreover, the US Entity List ban on one of the joint venture companies, for all intents and purposes, has made the project dead. The Chinese Hygon Dhyana x86 processors will still be in use by governments and other such organizations for a number of years to come, but this is bound to end up one of the oddest annals of the history of semiconductors.
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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.