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Cerebras launches Qwen3-235B, achieving 1.5k tokens per second

cerebras.ai

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Re: Cerebras launches Qwen3-235B, achieving 1.5k tokens per second

#12
post #6
post #4

Very impressive speed. With a context window of 40K however, usability is limited.

Post says 131k context though? What did I miss?

The PR confuse a but 32k/64k and 131k if paid API.

Also this model https://huggingface.co/Qwen/Qwen3-235B-A22B

Is native 32k. So the 64k and 131k use ROPE that is not the best for effective context.

While https://qwenlm.github.io/blog/qwen3-coder/ it's 256k native https://huggingface.co/Qwen/Qwen3-Coder-480B-A35B-Instruct.

Re: Cerebras launches Qwen3-235B, achieving 1.5k tokens per second

#13
post #11

With this kind of speed you could build a large thinking stage into every response. What kind of improvement could you expect in benchmarks from having say 1000 tokens of thinking for every response?

Thinking can also make the responses worse; AIs don't "overthink", instead they start throwing away constraints and convincing themselves of things that are tangential or opposite to the task.

I've often observed thinking/reasoning to cause models to completely disregard important constraints, because they essentially can act as conversational turns.

Re: Cerebras launches Qwen3-235B, achieving 1.5k tokens per second

#14
I'm eagerly awaiting for Qwen 3 coder being available on Cerebras.

I run plenty of agent loops and the speed makes a somewhat interesting difference in time "compression". Having a Claude 4 Sonnet-level model running at 1000-1500 tok/s would be extremely impressive.

To FEEL THE SPEED, you can either try it yourself on Cerebras Inference page, through their API, or for example on Mistral / Le Chat with their "Flash Answers" (powered by Cerebras). Iterating on code with 1000 tok/s makes it feel even more magical.

Re: Cerebras launches Qwen3-235B, achieving 1.5k tokens per second

#15

I'm eagerly awaiting for Qwen 3 coder being available on Cerebras. I run plenty of agent loops and the speed makes a somewhat interesting difference in time "compression". Having a Claude 4 Sonnet-level model running at 1000-1500 tok/s would be extremely impressive. To FEEL THE SPEED, you can either try it yourself on Cerebras Inference page, through their API, or for example on Mistral / Le Chat with their "Flash An…

Same.

However, I think Cerebras first needs to get the APIs to be more openAI compliant. I tried their existing models with a bunch of coding agents (include Cline which they did a PR for) and they all failed to work either due to a 400 error or tool calls not being formatted correctly. Very disappointed.

Re: Cerebras launches Qwen3-235B, achieving 1.5k tokens per second

#17
post #11

With this kind of speed you could build a large thinking stage into every response. What kind of improvement could you expect in benchmarks from having say 1000 tokens of thinking for every response?

My use-case would probably be of autocompacting the context of another LLM. I've been using Claude Code a lot recently, and feel that it generally gets better at handling my codebase once it uses up a lot of context (often >50%), but then it often runs out of context before finishing the task. So I'd be very interested in something that runs behind the scenes and compacts it to e.g. ~80%.

I know that Letta have a decent approach to this, but I haven't yet seen it done well with a coding agent, by them or anyone else. Is there anyone doing this with any measure of success?

Re: Cerebras launches Qwen3-235B, achieving 1.5k tokens per second

#18
Cerebras is truly one of the maddest technical accomplishments that Silicon Valley has produced in the last decade or so. I met Andy seven or eight years ago and I thought they must have been smoking something - a dinner plate sized chip with six tons of clamping force? They made it real, and in retrospect what they did was incredibly prescient

Re: Cerebras launches Qwen3-235B, achieving 1.5k tokens per second

#19
If this is the full fp16 quant, you'd need 2TB of memory to use with the full 131k context.

With 44GB of SRAM per Cerebras chip, you'd need 45 chips chained together. $3m per chip. $135m total to run this.

For comparison, you can buy a DGX B200 with 8x B200 Blackwell chips and 1.4TB of memory for around $500k. Two systems would give you 2.8TB memory which is enough for this. So $1m vs $135m to run this model.

It's not very scalable unless you have some ultra high value task that need super fast inference speed. Maybe hedge funds or some sort of financial markets?

PS. The reason why I think we're only in the beginning of the AI boom is because I can't imagine what we can build if we can run models as good as Claude Opus 4 (or even better) at 1500 tokens/s for a very cheap price and tens of millions of context tokens. We're still a few generations of hardware away I'm guessing.

Re: Cerebras launches Qwen3-235B, achieving 1.5k tokens per second

#20

I'm eagerly awaiting for Qwen 3 coder being available on Cerebras. I run plenty of agent loops and the speed makes a somewhat interesting difference in time "compression". Having a Claude 4 Sonnet-level model running at 1000-1500 tok/s would be extremely impressive. To FEEL THE SPEED, you can either try it yourself on Cerebras Inference page, through their API, or for example on Mistral / Le Chat with their "Flash An…

I just set up Groq with Kimi K2 the other day and was blown away by the speed.

Deciding if I should switch to Qwen 3 and Cerebras.

(Also, off-topic, but the name reminds me of cerebrates from Starcraft. The Zerg command hierarchy lore was fascinating when I was a young child.)

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