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400 GB/s is insane memory bandwidth. I think a m5.24xlarge for instance has something around 250 GB/s (hard to find exact number). Curious if anyone knows more details about how this compares.

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Its still a bit unclear how much of the bandwidth the CPUs can use (as opposed to the GPUs)

I think Anandtech showed a M1 P-core could max out 50+GB/s on it's own, so 8 P-cores alone likely can use 400GB/s. With both the CPU+GPU, they'd be sharing the BW. A 3060/6700XT have ~360-384 GB/s, so game benchmarks should be interesting to see at high res.

Additionally, do the 24-core GPU and 32/64 GB RAM variants of the M1 Max all have 4 128-bit memory controllers enabled? The slide seems to just say 400GB/s (Not "up to"), so probably all Max variants will have this BW available.

The value is in the power efficiency here (N5P?+), and if you can afford a $3k+ laptop.

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