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Comment by guelo | Hacker News Reader

Why is AMD making these chips with 14nm transistors instead of using TSMC's 7nm stuff? AMD is only catching up to Intel because Intel's 10nm has been delayed so much, but if Intel can ever figure out their 10nm process they'll be in the lead again.

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AMD use 14nm for the IO die and 7nm for the compute chiplets. 10nm won't help much - after all the security fixes that Intel have had to implement, AMD have the IPC advantage.

And further, "nm" these days are marketing numbers. It's totally possible that AMD's 7nm isn't directly comparable to a 7nm (or 10nm) Intel process.

Apparently it is 7nm. https://www.tomshardware.com/reviews/amd-ryzen-threadripper-...

Their biggest win over Intel was using 14nm IO bridge to connect 7nm CPU cores ("chiplets") in the Ryzen 3000 era. They use 14nm for IO where there's little benefit to the process shrink so they can save the lower-yielding 7nm process for where it counts: cores.

And I think you're missing the biggest bit, there - each set of 8 cores is its own die. That means that if they have a yield of 95% for that one die, they'll have a yield of 95% for a 64 core monster, too. Compare with Intel, where octupling the die area means their yields would go from 95% to 0.95^8 = 66%. (And if they had 50% yields to start, Intel would end up with 0.4% yields after octupling - AMD would still have 50% total)

This can be a bit confusing, basically some parts within the CPU package 7nm dies and other parts are 14nm dies. The chiplets that are the CPU core are the prior, interconnects (or the I/O die) is the latter.

What are you talking about? Zen 2(Ryzen 3000) uses 7 nm.

It's a composite chip (chiplets) with different parts made using different processes for various reasons.

As a fun fact, IBM's newest (and quite impressive) mainframe, the z15, is still using the same Global Foundries 14nm process the z14 did. The next generation (including POWER10) will probably be 7nm, but not come from GF.

It runs above 5 GHz.

>if Intel can ever figure out their 10nm process they'll be in the lead again.

What are you basing this claim on?

All we know Zen2 targeted beating an hypothetical 10nm Intel CPU which has not shown up.

As it has not shown up, it remains hypothetical. Wild what-ifs.

AFAIK is Threadripper 2 12nm. I guess its because they can deliver very high speed with that process, without cannibalizing the already overtaxed TSMC-7nm Lines.

Threadripper-users dont care that much about energy efficiency - and its a small market, which gets cannibalized by the 3950X in the new generation.

It's 7nm, similar to Rome.

Threadripper 2 was 12nm, Threadripper 14. The new TR3 will be 7nm

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