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Advances in semiconductors are feeding the AI boom

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31–40 of 124 posts

Re: Advances in semiconductors are feeding the AI boom

#31

When the limits of digital reaches the boundary of physics, Analogue is going make a comeback. Human brain feels nearer to Analogue than Digital. I will be surprised to reach AGI without nearing the Order-of-Magnitude of brain processing. We need that ONE paper on analogue to end this quest of trillions and counting transistors.

>We need that ONE paper on analogue

https://www.analog.com/en/resources/analog-dialogue/articles...

Re: Advances in semiconductors are feeding the AI boom

#32
post #8

Yeah I also think that the impact of better hardware generates a visible lead in quality in the models that are released, for example: companies like OpenAI have had access to large quantities of H100 for a few months now and Sora is being presented, something I would not have believed a year ago, I would also believe that Claude 3 models were trained on H100, DBRX was trained on 12T tokens, a big difference compared…

> companies like OpenAI have had access to large quantities of H100 for a few months now and Sora is being presented From what I could tell from Nvidia's recent presentation, Nvidia works directly with OpenAI to test their next gen hardware. IIRC they had some slides showing the throughput comparisons with Hopper and Blackwell, suggesting they used OpenAI's workload for testing. H100's have been generally available (…

Very interesting, I guess it does make sense that GPT-4 was also trained on the Hopper architecture.

Re: Advances in semiconductors are feeding the AI boom

#33

Wild that the human brain can squeeze in 100 trillion synapses ( very roughly analogous to model parameters / transistors) in a 3lb piece of meat that draws 20 Watts. The power efficiency difference may be explainable by the much slower frequency of brain computation (200 Hz vs. 2GHz). My impression is that the main obstacle to achieving a comparable volumetric density is that we haven't cracked 3d stacking of integr…

I think biggest difference is millions of years evolutionary development. That's a lot of time difference.

Re: Advances in semiconductors are feeding the AI boom

#34

We already have a 4 trillion transistor "GPU" in the Cerebras WSE-3 (wafer-scale engine), used in Cerebras' data centers. https://www.youtube.com/watch?v=f4Dly8I8lMY

how many regular sized GPU (say 4080 or nvidia L4) dies can be cut out from a full-sized wafer? I suppose thats what OP means by reaching integration density of 1T GPU.

here's some discussion about yields for H100 per wafer. I'd assume a 4080 is smaller? regardless, the calculator is supplied.

https://news.ycombinator.com/item?id=38588876

Re: Advances in semiconductors are feeding the AI boom

#35

We already have a 4 trillion transistor "GPU" in the Cerebras WSE-3 (wafer-scale engine), used in Cerebras' data centers. https://www.youtube.com/watch?v=f4Dly8I8lMY

how many regular sized GPU (say 4080 or nvidia L4) dies can be cut out from a full-sized wafer? I suppose thats what OP means by reaching integration density of 1T GPU.

I think the whole premise of TFA is flawed, as there already chips with way more than a trillion transistors (as GP points out).

Arguing about what is the size limit to consider something a GPU or not is a bit like bikeshedding.

As to why wouldn't a supercomputer be considered for this? Because it's not a single chip.

Re: Advances in semiconductors are feeding the AI boom

#37

Wild that the human brain can squeeze in 100 trillion synapses ( very roughly analogous to model parameters / transistors) in a 3lb piece of meat that draws 20 Watts. The power efficiency difference may be explainable by the much slower frequency of brain computation (200 Hz vs. 2GHz). My impression is that the main obstacle to achieving a comparable volumetric density is that we haven't cracked 3d stacking of integr…

> is it just that we haven't cracked 3-d stacking of integrated circuits yet?

Yes. If we could stack transistors in the Z dimension as closely as we do in X and Y, we'd easily exceed the brains density.

Re: Advances in semiconductors are feeding the AI boom

#38

Wild that the human brain can squeeze in 100 trillion synapses ( very roughly analogous to model parameters / transistors) in a 3lb piece of meat that draws 20 Watts. The power efficiency difference may be explainable by the much slower frequency of brain computation (200 Hz vs. 2GHz). My impression is that the main obstacle to achieving a comparable volumetric density is that we haven't cracked 3d stacking of integr…

No neurons are the equivalent of transistors. Synapses are the equivalent of connections between transistors. The total neurons are about 100 Billion but the connections are 100 Trillion. A neuron can have up to 10,000 synapses, while a transistor can have on average only about 3. Impressive nonetheless on power efficiency.

Re: Advances in semiconductors are feeding the AI boom

#39
post #13

Earlier quoted context omitted.

What's amazing is that the human brain does it all on the equivalent of like 20 watts of power. That's basically a couple of LED light bulbs.

Is there a comparison of power efficiency of human brain doing 50 digits multiplication vs a multiplier circuit doing it?

I think the problem here would be figuring out how much of the brain's power draw to attribute to the multiplication. A brain is more akin to a motherboard than a single CPU, with all kinds of I/O, internal regulation, and other ancillary stuff going on all the time.

Re: Advances in semiconductors are feeding the AI boom

#40

Wild that the human brain can squeeze in 100 trillion synapses ( very roughly analogous to model parameters / transistors) in a 3lb piece of meat that draws 20 Watts. The power efficiency difference may be explainable by the much slower frequency of brain computation (200 Hz vs. 2GHz). My impression is that the main obstacle to achieving a comparable volumetric density is that we haven't cracked 3d stacking of integr…

Ignoring for the moment that transistors and synapses are very different in their function, the current in a CPU transistor is in the milliampere range, whereas in the ion channels of a synapse it is in the picoampere range. The voltage differs by roughly a factor of ten. So the wattage differs by a factor of 10^10.

One important reason for the difference in current is that transistors need to reliably switch between two reliably distinguishable states, which requires a comparatively high current, whereas synapses are very analog in nature. It may not be possible to reach the brain’s efficiency with deterministic binary logic.

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