Cerebras CS-4

(cerebras.ai)

79 points | by sunils34 2 hours ago

13 comments

  • sva_ 0 minutes ago
    > enabling massive clusters and models with more than 50 trillion parameters
  • aneryu 3 minutes ago
    It would be even better if a version available to individual users were released soon.
  • syntaxing 57 minutes ago
    I think the fun takeaway from this is that GPT 5.4 is probably 45B active parameters and GPT 5.6 Sol is closer to 50B.
    • logicallee 21 minutes ago
      (Where did you see that?)

      This was also interesting: "CS-4 delivers more than 1,000 tokens per second on models exceeding 10 trillion parameters." Was it known that there were 10 trillion parameter models in use?

      I think the frontier providers keep the size of their models carefully hidden.

      • ewild 19 minutes ago
        It's rumored fable is around that 10T number
        • walrus01 11 minutes ago
          If this is true, it's even more impressive that some of the open weight models that are <3.5T in size, approx 33% of its size, are within a few points of it in the artificial analysis leaderboard.
  • reilly3000 34 minutes ago
    > CS-4 delivers more than 1,000 tokens per second on models exceeding 10 trillion parameters

    Oops did they just out GPT-5.6 sol’s parameter count?

    • sho 11 minutes ago
      Sol is supposed to be 5T according to rumour. The imminent Astra is allegedly 10
    • whatever1 24 minutes ago
      I mean we kinda know the frontier models are multi trillion parameter models. The only open weights that are close to the frontier are that size too
  • sreekanth850 39 minutes ago
    AMD along with cerebras may probably compete with NVIDIA monopoly in near future. Also, NVIDIA will have competition form multiple companies. Just my prediction.
  • ethanzhang1024 20 minutes ago
    If cerebars is performing well, why didn't its predecessor, server S-3, become the largest API token provider on OpenRouter, surpassing the official model releases?
    • walrus01 17 minutes ago
      Without having any inside information, one possible theory:

      All or a vast majority of of the cerebras manufacturing capacity was going to a few companies that aren't publicly available inference providers on openrouter, for their own internal use.

      or

      The asking price of the S-3, no matter how speedy it might be, for small/medium size customers made it economically prohibitive to purchase and use to sell public inference vs. buying more common nvidia b200 or whatever.

    • smallerize 14 minutes ago
      If you're willing to pay a significant premium for latency, why use openrouter? And anyway Cerebras only supported a few specific models.
    • doctorpangloss 18 minutes ago
      it only takes ~445 GB300 NVL72 (about $22b) to run ALL of openrouter demand for a year. Microsoft rolled out $32b of DC 2026Q1.

      imo the issue is that most openrouter demand is inauthentic activity (things that anthropic and openai models will refuse to do like pretend to not be bots when interacting with humans)

  • anonymous_user9 1 hour ago
    Conspicuously missing: power consumption figures
    • wmf 55 minutes ago
      162 kW
      • walrus01 22 minutes ago
        I guess we know why there's a fair bit of investment money going into small modular nuclear reactor startups now.
      • roughly 23 minutes ago
        God, I was going to ask if this could be deployed in a standard existing datacenter, but I guess that answers that question.
      • xattt 51 minutes ago
        I presume per rack?

        Can you imagine something radiating that much energy into a space in your home?

        • walrus01 23 minutes ago
          It's mandatory liquid cooling, so it's meant to be attached to a specialized liquid cooling loop that gets the heat outside the building.

          This is far beyond the practical maximums of like 10 to 15kW per 44U cabinet front to rear air cooling for 'regular' rackmount server stuff.

        • wmf 43 minutes ago
          I guess because I have actually set foot in a data center I don't imagine literally every product in my home.
    • logicallee 18 minutes ago
      "10x more throughput per watt than CS-3"
  • 9cb14c1ec0 1 hour ago
    Just a reminder for everyone that we are only several years and 3 or 4 iterations into hardware being optimized for LLMs. We should all expect orders of magnitude improvement in speed and/or cost over the next 5 years. Then we can have fun conversations about "unlimited" "intelligence" and about what the price wars and profit margins of consumer AI products are when your average ChatGPT user costs the company $0.10 per month.

    > CS-4 delivers more than 1,000 tokens per second on models exceeding 10 trillion parameters

    Wow!

    • SwellJoe 1 hour ago
      And, the software side isn't finished being optimized, either. We've seen with Qwen 3.8 27B and DeepSeek V4 Flash 0731 and GLM 5.3 that quite small models can pack a punch. Intelligence density will improve, efficiency of kernels will improve, efficiency of KV caching and MTP will improve, algorithms for splitting workloads across compute units will improve.

      It'll all be as cheap as DeepSeek was before the price hike. And, it'll become more and more realistic to run near-frontier intelligence on personal devices.

    • rvz 52 minutes ago
      Congratulations! You have just realized that the AI data center build out is a total scam, built on both the insurmountable trillions of debt, and the assumption that only GPUs are all we need to continue scaling.

      There exist other AI accelerators (TPUs, ASICs) that perfectly exceed the throughput that LLMs need to scale as well. But the true solution is more software optimizations. There's a tiny handful of them but more needs to be discovered so that we can reduce building hundreds of more data centers as the alternatives mature.

      As better software becomes more useful for the alternative AI hardware for developers with LLMs running efficiently you then would have more choices of hardware to run your LLMs on rather than just only GPUs.

      • blovescoffee 34 minutes ago
        TPUs and ASICs run in data centers too. Your argument only holds true if there's some satisfied limit to demand for inference. If not, data centers will continue to spring up to host more and more agents. Even if agents were running on hardware and software as efficient as the human brain, its conceivable we want trillions of them running at any given time which would require data center scale.
        • georgeecollins 2 minutes ago
          Everything has some satisfied limit to demand, often depending on the price. If you assume there will never be any satisfied limit to demand for inference at any price you can justify any investment.
      • jryle70 4 minutes ago
        Huh, why I'm not surprised that HN is full of opinions confidently stated without any numbers or resources to back up?

        > built on both the insurmountable trillions of debt, and the assumption that only GPUs are all we need to continue scaling.

        Insurmountable according to whom? And who assume that only GPUs are all we need to continue scaling? Google, Amazon, Microsoft, Meta and OpenAI, all have or plan custom non-GPU AI chips. Do they plan to use them not for scaling?

      • skyberrys 24 minutes ago
        I wonder what this looks like in 5 years... Will there be a massive push to repurpose these giant boxes into housing? Will they get turned back into the farm land from where they came? When a data center goes bust, what happens to the parts left behind?
        • gpm 15 minutes ago
          I'd think the infrastructure would tend towards factories, smelters, and so on. Industrial things that have reasonably high power demands, can use the building, and don't care about the lack of windows.

          They're typically not built where you want housing, and the buildings are distinctly the wrong shape.

          If you can't use the power infrastructure profitably my next thought would be warehousing.

          But also... we've seen a pretty continually increasing demand for compute. Even if AI busts a bit (or becomes a bit more efficient) I bet most data centres stay data centres, just less profitable ones.

    • api 1 hour ago
      This is part of why I think the data center build-out is a bubble. We've barely scratched the surface when it comes to hardware optimization. We'll see exponential improvements in energy efficiency and speed over the next decade. Exponential, not linear.

      GPUs really aren't that great for AI. They just happen to be the best chips we have in mass production right now for this work load, and it takes time to field new designs. Basically every chip engineer on the planet is working on this right now.

      • mindwok 59 minutes ago
        Whether it's a bubble or not depends on how much the demand for compute and the type of workload keeps growing, though.

        If AI tends to be something used mainly in ideation and development, which is how a lot of people use it today, then once consumer hardware gets good enough you could see a bunch of the current data centre workloads move onto consumer devices.

        But if AI starts being used more in repeatable, operational workloads I think it makes sense to have significant cloud infrastructure for it. TBH I haven't seen much of this, and I've been skeptical about people using agents for much of anything when it can be done with just software. But we are starting to see more of this kind of workload, like the taggable Claude in your slack etc that people seem to really love.

      • winrid 1 hour ago
        On the plus side, lots of cheap servers to swoop up :)
        • sroussey 49 minutes ago
          But power hungry.

          In that 5+ year timeline, the compute per watt could change by three orders of magnitude.

          GPUs are to LLMs what CPUs are to gaming — not a good fit.

  • gpm 51 minutes ago
    Is it just me or is it bizarre that they're advertising old open-weight models.

    GLM 4.7 (December 2025) not 5 (Feb) 5.1 (April) or 5.2 (June). 5.3 (4 days ago) is, to be fair, not open weights yet... but there's a lot since 4.7.

    Kimi K2.7 (April) not K2.7-code (June) or K3 (July).

    Gemma 4 (April), Llama (April), and gpt-oss (August 2025) are up to date, but old (for models).

    Meanwhile the closed source GPT 5.6 sol is up to date (June)...

    Should potential purchasers take away from this that they're not going to be able to run recent models unless they front the cost of developing software or something?

    • eli 47 minutes ago
      I think they run whatever models they get paid to run. But mostly from enterprise. They are clearly not interested in consumer dollars.
      • gpm 42 minutes ago
        I mean the product is a server rack and while there's no advertised price I would assume it's six figures. So yes, an enterprise product.

        But even an enterprise is going to care about the difference between "we can run the model we want with support from the manufacturer" and "we have to purchase the product, and then spend another 6 figure sum having developers port a recent model to the product to use it".

        • WarmWash 38 minutes ago
          I feel like 6-figures would be the clearance price on it...
          • oceanplexian 11 minutes ago
            6 figures is a single mid range Xeon or Epyc server these days.
  • 4k0hz 1 hour ago
    > Introducing the all new Cerebras CS-4, a revolutionary rack-scale solution that delivers upto 30x faster inference compared to GPUs, enhanced economics, and a simple path todeploy [sic] hyperscale capacity.

    Did nobody proofread this?

    • algoth1 51 minutes ago
      If they had ask Claude it would probably look like this: Introducing the all new Cerebras CS-4, a revolutionary rack-scale solution that delivers up to 30x faster inference compared to GPUs, enhanced economics, and a simple path to load-bearing hyper scale capacity.
      • jm4 47 minutes ago
        That's unusually honest and the sharpest thing in this thread.
        • wren6991 2 minutes ago
          You're underselling it, and here's why.
    • SoMomentary 45 minutes ago
      Sometimes I wonder if mistakes are now used to indicate the possibility that a human actually wrote it.
      • ceejayoz 27 minutes ago
        There’s been a spate of Reddit AI bots using all lower case in hopes of evading detection.

        It’s still incredibly obvious.

    • geodel 57 minutes ago
      Maybe it is just part of their "compact design".
    • dpkirchner 52 minutes ago
      An error no frontier LLM would make, eh
  • lostmsu 28 minutes ago
    KV caching status?

    What's the point of 1000tok/s if you have to do prefill on every agentic turn which at 100k depth would make it 1.5 min latency every turn?

    • walrus01 21 minutes ago
      Information about RAM type/size and connection topology of the RAM to be used for context cache seems to be conspicuously absent from the slick looking marketing materials.
      • gpm 7 minutes ago
        There's a few more details at the bottom of this page: https://www.cerebras.ai/blog/introducing-cerebras-cs-4

        44GB on-chip-sram * 3 chips. Per chip: 43.2 PB/s memory access + 53.5 PB/s on-chip fabric bandwidth + 2.4 Tbits/s "IO" bandwidth (I think that means their RoCE v2 RDMA over Ethernet interface).

        I suspect there might be a certain amount of customization for how much RAM they attach when you order it.

  • tamimio 29 minutes ago
    I wonder what are the benchmarks of hashcat on different hashes.
  • OutOfHere 1 hour ago
    Five years from now, I don't know why anyone will still be using Nvidia for inference. Note that Cerebras is for inference only, not for training.

    I understand that Cerebras has competition, but this bodes even more poorly for Nvidia for inference. Nvidia may still have a role to play for training, however.

    • wmf 51 minutes ago
      Cerebras is only claiming ~2x the performance of Groqvidia which usually isn't enough for people to switch.