[PeterStuer]

Is this on chip memory? From the 800GB/s I would guess more likely a 512bit bus (8 channel) to DDR5 modules. Doing it on a quad channel would just about be possible, but really be pushing the envelope. Still a nice thing.

As for practicality, which mainstream applications would benefit from this much memory paired with a nice but relative mid compute? At this price-point (14K for a full specced system), would you prefer it over e.g. a couple of NVIDIA project DIGITS (assuming that arrives on time and for around the announced the 3K price-point)?

[zitterbewegung]

NVIDIA project DIGITS has 128 GB LPDDR5x coherent unified system memory at a 273 Gb/s memory bus speed.

[bangaladore]

It would be 273 GB/s (gigabytes, not gigabits). But in reality we don't know the bandwidth. Some ex employee said 500 GB/s.

You're source is a reddit post in which they try to match the size to existing chips, without realizing that its very likely that NVIDIA is using custom memory here produced by Micron. Like Apple uses custom memory chips.

[PeterStuer]

Yes, but for the price of that single M3 ultra I could have 4 of those GB10's running in a 2x2 cluster with the full NVIDIA stack supported (which is still a big thing)

So M3 preference will depend on whether a niche can significantly benefit from a monolitic lower compute high memory vs higher compute but distributed setup.

[MBCook]

Unless something had changed its on package, but not the same die.