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Comment by TwoNineA | Hacker News Reader

Interesting, according to Anandtech, there might be space for something else on the package:

https://images.anandtech.com/doci/13829/cpu44.jpg

Maybe a second Zen2 die?

> “Some people may have noticed on the package some extra room,” she said with a chuckle. “There is some extra room on that package and I think you might expect we will have more than eight cores.”

Taken from: https://www.pcworld.com/article/3332205/amd/amd-ceo-lisa-su-...

Since Rome (their server part) uses 8 chiplets for 64 cores it makes sense.

When Rome was presented last year users also speculated about GPU and FPGA chiplets. Playstation 5 rumors also speculate about chiplets to keep the price to performance ratio as low as possible (though I wonder about latency which games are sensitiv to). So going all in on chiplets and reusing them for everything would make sense for AMD.

I don't disagree with your takeaway, but one nit: games are less sensitive to latency than they are to unexpected latency. You can deal with latency through a number of techniques so long as it's consistent. (IIRC, this is one of the reasons for some of the interesting hardware on the Xbox 360 shrinks - reconfiguring the CPU/GPU package meant that the hardware team had to gimmick it such that games didn't have to suddenly deal with less latency than they'd been intended for.)

thanks for the insight, I only ever read "games are sensitive to latency" but not exactly in what way.

No problem. Just consider it as a scheduling problem. If you know it takes N cycles to load a register (and to be clear, this is no longer something most game developers have to actively care about...though engine developers might...though on very modern consoles even this often ends up abstracted from most engine developers), having that register now be populated at (N-2) or (N+2) cycles might be Very Bad. On the other hand, if you now know that it will populate, always, in (N+4) cycles, you can just work with that.

Probably for an iGPU for the budget model all in one chips.

Take this how you will, but his leakers have been very accurate in the past.

Seems possible to put 2 dies there with lower core counts to be able to use the chips (eg 4 + 4). As you say, it's also possible for 8 + 8, and probably 6 + 6 combinations. Also possible to put a GPU there for their G series.

https://www.youtube.com/watch?v=PCdsTBsH-rI

On reddit there have been a lot of leaks. Pointing to either 12c or 16c variants. Additionally room for the gpu, and maybe some hbm.

> maybe some hbm

Think of 3+1GB of scratch memory or L4, this could feed a GPU and not compete with main memory access. Or for notebook or game use, it would need less 100 active pins, vastly simplifying pcb design and costs.

There were some rumors before this announcement that AMD would announce SKUs with 1 CPU die (6-8 cores activated) + 1 GPU die or with 2 CPU dies (8-16 cores activated). But AMD didn't announce any SKUs - seems they're a bit behind on schedule.

They are launching processors in the middle of the year. If they reveal too much 4-6 months out, Intel has way too much time to adjust their prices, change their marketing, put pressure on suppliers, etc.

This leaves a lot of guesswork. Intel has to be prepared for multi-chip, chip + CPU, faster chips, slower chips (maybe this was a golden sample), etc which makes it much harder to adjust in preparation.

Also, if they reveal too much prospective buyers might be incentivized to delay their purchase. As stupid as that might sound, it is a thing.

It even has a name: Osborne effect

https://en.m.wikipedia.org/wiki/Osborne_effect

Probably just keeping the chiplet orientation wrt to the iochip (as compared to their bigger products) simplify design and validation.

You'd see the vias for the empty chip if it were planned to share the interposer among chip combination SKUs.

On /r/amd a user posted a different photo [0] taken from the stream which - to a layman like me - looks like there is circuitry (or whatever?) for a second chiplet.

[0] https://i.imgur.com/gzXaoJz.png

Or integrated graphics.

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