It's Arm based, although they barely mention that.

Yes the lack of transparency on ARM architecture and the obfuscation of the RAM capacity with just the slot information is annoying. Not sure if it is deliberate to sell this at a premium to "mainframe" customers or whether its just their marketing folk not being on the ball. Fascinated by the fact Japan has a 2nm process node but I suspect that too is marketing. Perhaps the 2nm portion of the chip is done at TSMC and the rest of the package done in Japan or something like that. It's not like there's a plethora of 2nm Fabs around the planet to choose from.

Reading of JASM (TSMC/Sony subsidiary) it seems they're planning on producing at least 3nm chips there in their expansion plans.

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It looks to me like it is an AI optimized HPC CPU and while HPC CPUs are actually quite fast, they are not particularly well suited for transformer based neural networks.

It's weird that they don't give out any of the interesting numbers like number of memory channels, how much SRAM they have (CPUs tend to have more of it) or what their expected performance is going to be.

They did a detailed presentation at Hot Chips.

See e.g.:

https://chipsandcheese.com/p/hot-chips-2026-fujitsus-monaka-...

They have provided far more details than companies like Apple or Qualcomm.

Looks good for HPC but the AI performance is only good against other CPUs. Even Intel GPUs can beat the quoted numbers within that power envelope.

They actually do not in that article. I had to look elsewhere to find that out. Weird, one would expect that a big announcement like this would probably need to be vetted against licensing agreements with Arm that would probably want that fact to be prominently highlighted in press releases.

It is in the article - they cite "SVE2" support

Yeah, searched the page for common architectures (x86,arm and Sparc since it was Fujitsu) since it'd seem silly to use a totally novel architecture but didn't find anything until noticing SVE2.

Fujitsu has a long history of designing their own micro but using a standard ISA for HPC. Used to be SPARC, now it is ARM. IIRC Fujitsu were the main architects behind the SVE ARM extension.

If they didn't mention SVE2, I wouldn't have known either... that would make it arm9 at the earliest...

Quick Google result is it’s basically a Neoverse V2 system, so yeah, armv9.

Edit: it’s funny because this article from 2021 mentioned Fujisu precisely https://siliconangle.com/2021/03/30/arm-unveils-armv9-archit...

No it is not at all Neoverse V2, which is obsolete and has much lower performance.

It is a custom Armv9.3-A design (same ISA like the Arm C1 CPUs from the flagship smartphones of 2026), but it has double-width execution units for SVE2 (i.e. 256-bit width, vs. 128-bit for the other Arm CPUs) and it has some ISA extensions for AI/ML, e.g. instructions for inference with FP8 (BF16 is already supported by the standard Arm ISA).

Despite the fact that Armv9.3-A may include SME (scalable matrix extension, like in the Apple CPUs and in the Arm C1 CPUs), Fujitsu did not mention SME, so I assume that they did not implement it and they rely on their enhanced SVE2 (which is not surprising, while the origin of Arm SME is at Apple, the origin of Arm SVE is at Fujitsu).

Monaka-X will include SME2 but it didn't make the cut for first-gen Monaka

That was regarding the HPC Fugaku , this is next generation

But Arm is owned by SoftBank, a Japanese conglomerate.

(I think Japanese sovereignty is the main point of the article.)

Interesting to note that Fujitsu did this when the SPARC architecture was popular: they enhanced/developed a CPU for the same ABI.

Seems they have decided they don’t want to create their own architecture, but take the popular architecture and build on it.

Thanks kinda how Japan works. Inventing something new is hard, but taking something that's a cool idea and making it actually usable is well within their wheelhouse.

See: - Blue LEDs - Quartz Watches - Lithium-ion Batteries - Bidets

I'm sure there's plenty of other stuff invented in Japan, but that's really beside the point.

The industry is now mature enough that nobody really wants the headache of a new architecture at this point in time, Risc-V got a pass for being a grassroots movement growing out off FPGA's since the IP situation was more or less clear or even predatory with all existing architectures, Power, Sparc,SuperH,68k,etc are buried for good reasons.

POWER is still holding on just barely but I do suspect that IBM are looking to sunset it in the next few years.

Given that IBM just announced a dual-ISA mainframe with support for both z/arch and ARM, they might indeed be looking to sunset POWER.

Powers not dead yet! IBM is still clinging to it and I can't blame them, it's a pretty good ISA

Yep, I have said it for a good 20 years now.

POWER/PowerPC is what happens when you take a brilliant design to execute it poorly. x86 is when you take a poor design and execute is brilliantly.

PPC could have any number of merits, the 2 nail in the coffin imho is that the community/implementations seems to have held on to a big-endian tradition whilst the mass of users/developers firmly shifted to little-endian when Apple went to x86 and that IBM didn't push it properly open in the 2005-2008 timeframe when PS3/Xbox360 were still relevant (OpenPower seems to have been created in 2013, after the creation of Risc-V and PS4/XboxOne going to x86).

PPC was great with the G4, it was much better than the P3. Intel with P3 based-Core Duos won against the G5.

UC Berkeley developed RISC-V, so no doubt their influence within the computer science academia sphere had something to do with it.

Dunno, I think Risc-V's simplicity gave it the initial popularity rush rather than being from a certain institution (the institution perhaps gave it visibility, but it does have own merits and no idea if other archs from the time had those?), don't remembere exactly but iirc it was possible to implement with a ridiculously small amount of FPGA gates. Conversly heard some rumblings that it had parts t hat were unsuitable for scaling up but it seems to have gained enough momentum for people to engineer past stuff like that.

I had this idea that Fujitsu was one of those Japanese conglomerates that had operations in all kinds of markets, from electronics to heavy earth moving equipment to air conditioners to locomotives. But that doesn't appear to be the case so I'm wondering which company I'm confusing them with.

Edit I think I was thinking of Mitsubishi.

Fujitsu was a telco equipment spinoff from Fuji Electric, so Fujitsu do/did make a lot of things that would be in a phone exchange building over its history, from air conditioners to terminals to actual mainframes. Just not as everything as Mitsubishi, which was a do-all procurement company for the new government when the Tokugawa stepped down.

About 25 years back here in Australia they were advertising Fujitsu air-conditioners, they had the promise of some like "They will get the air down to 17c in all conditions."

About a month later there was a summer heat wave and I went to a friends house who had just bought one. It was wild walking in from a 45c day into, as advertised, a 17c house. Had to give it to them, they lived up to the claim.

That they come from the telecom/server space, it makes sense they had a good eye for aircon engineering.

In Spain an aircon ad in TV joked by telling the viewer that "silence" in Japanese it's "Fujitsu".

Probably Panasonic. They're like the Apple of the B2B world. Except they also make everything

Fujitsu is basically the Japanese IBM.

I am in tech (okay now I am really wondering what % of people on here are NOT in tech). I have spent years in Japan for work, and ironically right now as I type this, I am sitting in a seat on JL2 from Tokyo to SFO. I worked with all of the large Japanese companies over the years and I can say Fujitsu has always been the most impressive, and to you comment, most like golden age IBM (I worked there for a brief time also). They, like IBM are most likely to have brilliant tech, and then shoot themself in the head for non-tech reasons.

The 1980s called, it wants its stereotypes back.

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Sun invented SPARC, Fujitsu just happened to be the last producer since they built mainframes on it. Reading it seems like they plan to stop producing Sparc processors and machines in a near timeframe so that makes this announcement less surprising.

For many years the Fujitsu SPARC implementations were much faster than the Sun SPARC implementations.

During the decade 1995-2005, until the 64-bit AMD Opteron servers with Linux offered an alternative that crushed any kind of SPARC CPU with Solaris by a much higher performance combined with a much lower price, the SPARC Sun or Fujitsu servers dominated the market for servers used to host the CAD/EDA design tools used in electronics engineering, for the design of integrated circuits or electronic equipment. This means that all the EDA software from vendors like Mentor, Cadence, Synopsis etc. was available only for Solaris. That kind of software could not be run on Windows, due to the 32-bit memory limit. During that time, whoever got Fujitsu servers instead of the sluggish Sun servers, was very lucky.

It was an issue of fundamentally differing directions.

In the mid-2000's, Sun decided to take SPARC towards designs with many small SMT cores. In the era of single-core processors, the UltraSPARC T1 had 8 cores x 4 threads per core. This was at the same time Intel released the Pentium 4 with hyper-threading, so it was an industry trend.

This of course works great for very specific applications, particularly considering efficiency, but is awful for others. Scientific computation was especially bad because the T1 had only one FPU for 8 cores.

Fujitsu's SPARC64 didn't go in this direction, and stayed with a conventional design (2 way SMT at most). Sun realized this and started to also sell the Fujitsu SPARC64 for customers who couldn't use the thread level parallelism, an arrangement that lasted until the end.

The idea of lots of slow cores is still a thing today: Intel's Sierra Forest Xeon is 144 E-cores.

1 FPU for 8 cores is wild, but then again they were selling webservers.

Still, iirc FPU's were silicon heavy back in those days and it'd be interesting to know how far ahead the foundries Sun and Fujitsu were, maybe it was simply a factor of being too far behind in the foundry race that left Sun with few options.

Intel's E-Cores still are functionally complete for most parts though (excl Avx512?)? Todays limits seems to be memory bandwidth and power and I guess many of the 144 core customers are in it for virtualization and servers?

Thanks. Looked for that in the article and couldn't find it.

What are the GPU capabilities?

Likely none? I believe they just don't give graphics out to non-x86 servers. If you mean GPU as in SIMD processor, I believe this is supposed to have it in forms of massive SIMD capabilities on CPU itself.

These things feel like, if they have any video output, it would be a single VGA port for if you REALLY need to get a signal from it.

x86 servers are like that. PC/AT memory map have the range for VRAM, but RS232C is optional, so you can't just have the RS232C and not VGA on an x86 as its debug/recovery interface.

Platform designers can make up their own memory maps, so non-x86 ones can just have UART I/O buffer and hardware interface wired up in whatever address you want and forgo VGA.

I have a 32bit SPARC machine on a shelf I got from a junk hardware shop, it has a DB25 for console. It's ok.

Thanks I was, of course, looking and very curious what their tool chain story will be.

Not mentioning the architecture is rather strange. Being Fujitsu I'd expect SPARC, but apparently not. Maybe we're reaching a point where some circles either don't care or just defaults to ARM?

Obviously they can just ignore the license in the future and continue development out of a local branch, but it's also a bit disingenuous to speak of "sovereign infrastructure" and then use licensed processor design.

It think we are now heading towards the final long term ISA setup. x86 and ARM at the top, ARM in the middle and RISC-V for smaller embedded machines that don't need the ARM toolchain.

Fujitsu dropped SPARC for HPC ~seven years ago with their A64fx. That's where ARM SVE comes from in the first place.

I feel old now.

Yes but it's their own design, not licensing Arm cores.

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