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TPUs vs. GPUs and why Google is positioned to win AI race in the long term

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181–190 of 328 posts

Re: TPUs vs. GPUs and why Google is positioned to win AI race in the long term

#181
post #153

Earlier quoted context omitted.

PyTorch is only part of it. There is still a huge amount of CUDA that isn’t just wrapped by PyTorch and isn’t easily portable.

... but not in deep learning or am I missing something important here?

Yes, absolutely in deep learning. Custom fused CUDA kernels everywhere.

Re: TPUs vs. GPUs and why Google is positioned to win AI race in the long term

#182
post #2

A question I don't see addressed in all these articles: what prevents Nvidia from doing the same thing and iterating on their more general-purpose GPU towards a more focused TPU-like chip as well, if that turns out to be what the market really wants.

It’s not binary. It’s not existential. What’s at stake for Nvidia is its HUGE profit margins. 5 years from now, Nvidia could be selling 100x as many chips. But its market cap could be a fraction of what it is now if competition is so intense that its making 5% profit margin instead of 90%.

Re: TPUs vs. GPUs and why Google is positioned to win AI race in the long term

#183
post #89

Earlier quoted context omitted.

Check the specs again. Per chip, TPU 7x has 192GB of HBM3e, whereas the NVIDIA B200 has 186GB. While the B200 wins on raw FP8 throughput (~9000 vs 4614 TFLOPs), that makes sense given NVIDIA has optimized for the single-chip game for over 20 years. But the bottleneck here isn't the chip—it's the domain size. NVIDIA's top-tier NVL72 tops out at an NVLink domain of 72 Blackwell GPUs. Meanwhile, Google is connecting 921…

Isn’t the 9000 TFLOP/s number Nvidia’s relatively useless sparse FLOP count that is 2x the actual dense FLOP count?

Correct --- found a remark on Twitter calling this "Jenson Math".

Same logic when NVidia quote the "bidirectional bandwidth" of high speed interconnects to make the numbers look big, instead of the more common BW per direction, forcing everyone else to adopt the same metric in marketing materials.

Re: TPUs vs. GPUs and why Google is positioned to win AI race in the long term

#184
post #56
post #54

Earlier quoted context omitted.

It’s true that architectures change, but they are built from common components. The most important of those is matrix multiplication, using a relatively small set of floating point data types. A device that accelerates those operations is, effectively, an ASIC for LLMs.

We used to call these things DSPs

This is quite accurate considering Google TPUs are VLIW machines.

Re: TPUs vs. GPUs and why Google is positioned to win AI race in the long term

#185

> It is also important to note that, until recently, the GenAI industry’s focus has largely been on training workloads. In training workloads, CUDA is very important, but when it comes to inference, even reasoning inference, CUDA is not that important, so the chances of expanding the TPU footprint in inference are much higher than those in training (although TPUs do really well in training as well – Gemini 3 the prim…

NVIDIA chips are more versatile. During training, you might need to schedule things to the SFU(Special Function unit that does sin, cos, 1/sqrt(x), etc), you might need to run epilogues, save intermediary computations, save gradients, etc. When you train, you might need to collect data from various GPUs, so you need to support interconnects, remote SMEM writing, etc. Once you have trained, you have frozen weights/fee…

Won't the need to train increase as the need for specialized, smaller models increases and we need to train their many variations? Also what about models that continuously learn/(re)train? Seems to me the need for training will only go up in the future.

Re: TPUs vs. GPUs and why Google is positioned to win AI race in the long term

#186
I don't think what the article writes about matters all that much. Gemini 3 Pro is arguably not even the best model anymore, and it's _weeks_ old, and Google has far more resources than Anthropic does. If the hardware actually was the secret sauce, Google would be wiping the floor with little everyone else.

But they're not.

There's a few confounding problems:

1. Actually using that hardware effectively isn't easy. It's not as simple as jacking up some constant values and reaping the benefits. Actually using the hardware is hard, and by the time you've optimized for it, you're already working on the next model.

2. This is a problem that, if you're not Google, you can just spend your way out of. A model doesn't take a petabyte of memory to train or run. Regular old H100s still mostly work fine. Faster models are nice, but Gemini 3 Pro being 50% of the latency as Opus 4.5 or GPT 5.1 doesn't add enough value to matter to really anyone.

3. There's still a lot of clever tricks that work as low hanging fruit to improve almost everything about ML models. You can make stuff remarkably good with novel research without building your own chips.

4. A surprising amount of ML model development is boots on the ground work. Doing evals. Curating datasets. Tweaking system prompts. Having your own Dyson sphere doesn't obviate a lot of the typing and staring at a screen that necessarily has to be done to make a model half decent.

5. Fancy bespoke hardware means fancy bespoke failure modes. You can search stack overflow for CUDA problems, you can't just Bing your way to victory when your fancy TPU cluster isn't doing the thing you want it to do.

Re: TPUs vs. GPUs and why Google is positioned to win AI race in the long term

#187
post #41

Google's real moat isn't the TPU silicon itself—it's not about cooling, individual performance, or hyper-specialization—but rather the massive parallel scale enabled by their OCS interconnects. To quote The Next Platform: "An Ironwood cluster linked with Google’s absolutely unique optical circuit switch interconnect can bring to bear 9,216 Ironwood TPUs with a combined 1.77 PB of HBM memory... This makes a rackscale…

That is comparing an all to all switched Nvlink fabric to a 3D torus for TPUs. Those are completely different network topologies with different tradeoffs. For example the currently very popular Mixture of Experts architectures require a lot of all to all traffic (for expert parallelism) which works a lot better on the switched NVlink fabric as opposed where it doesn't need to traverse multiple links in the torus.

This is an underrated point. Comparing just the peak bandwidth is like saying Bulldozer was the far superior CPU of the era because it had a really high frequency ceiling.

Re: TPUs vs. GPUs and why Google is positioned to win AI race in the long term

#189
post #166
post #163

Earlier quoted context omitted.

Not vibes. TPUs have fallen behind or had to be redesigned from scratch many times as neural architectures and workloads evolved, whereas the more general purpose GPUs kept on trucking and building on their prior investments. There's a good reason so much research is done on Nvidia clusters and not TPU clusters. TPU has often turned out to be over-specialized and Nvidia are pointing that out.

You say that like I d a bad thing. Nvidia architectures keep changing and getting more advanced as well, with specialized tensor operations, different accumulators and caches, etc. I see no issue with progress.

That’s missing the point. Things like tensor cores were added in parallel with improvements to existing computer and CUDA kernels from 10 years ago generally run without modification. Hardware architecture may change, but Nvidia has largely avoided changing how you interact with it.

Re: TPUs vs. GPUs and why Google is positioned to win AI race in the long term

#190
post #89
post #61

Earlier quoted context omitted.

100 times more chips for equivalent memory, sure.

Check the specs again. Per chip, TPU 7x has 192GB of HBM3e, whereas the NVIDIA B200 has 186GB. While the B200 wins on raw FP8 throughput (~9000 vs 4614 TFLOPs), that makes sense given NVIDIA has optimized for the single-chip game for over 20 years. But the bottleneck here isn't the chip—it's the domain size. NVIDIA's top-tier NVL72 tops out at an NVLink domain of 72 Blackwell GPUs. Meanwhile, Google is connecting 921…

I guess “this weight class” is some theoretical class divorced from any application? Almost all players are running Nvidia other than Google. The other players are certainly more than just competing with Google.
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