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0 pointstalldayo1y ago0 comments

> and per watt

Part of the advantage of using "one 4090" is that the max TDP is only 450w, as opposed to 5 M2 Ultras running at ~150w each. When you scale up to Nvidia's latest Blackwell architecture, I genuinely don't know how Apple could beat them on performance-per-watt. Buying M2 Ultras wholesale is probably cheaper than an NVL72 cluster, but certainly not what you'd want to use for Linux or maximizing AI-based performance-per-watt.

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hajile1y ago

You are missing the point. We're discussing if Apple can use their own chips more cheaply than buying Nvidia's chips.

The Max TDP is not actual peak power consumption. Gamer's nexus recorded 500w peak and almost 670w overclocked. Most reviews I've looked at seem to put peak power consumption around 550w.

M2 Ultra wasn't even mentioned and it uses more than 150w. The correct question would be about M3 Max as we have solid numbers on it. M3 Max uses around 100w when both the GPU and CPU are heavily utilized and less than that when only the GPU is used.

This means that Apple could run 5 of their M3 Max chips in the same peak power as the 4090. But wait, there's more. 4090 doesn't run in a vacuum. It requires a separate CPU setup and a couple hundred more watts.

That means we could power 7 or so M3 Max chips with that same amount of power.

Of course, this isn't the whole story. 4090 isn't a professional chip either (while Apple can bin and certify their own CPUs and know they're getting a server-grade chip) and the 4090 also doesn't have nearly enough RAM. H100 starts at $25,000 and goes up. Apple could buy 75-100 M3 Max chips for that kind of money. That's certainly a load more compute than H100 would offer. Blackwell will be even more expensive in comparison.

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