I don't doubt that they'll have some version of Navi 23 that's also had the clock speeds pushed as far as possible, but I don't think that necessarily matters for the point of this discussion.
Just look at a site like Silicon Lottery to see what I'm getting at since they have
posted statistics about how as you push clock speeds higher, fewer and fewer chips can reach those levels. Let's just use their results for the 10900K (comet lake) to illustrate this:
| Clock Speed | Percent of CPUs Capable |
|---|
| 4.8 GHz | 100% |
| 4.9 GHz | 99% |
| 5.0 GHz | 68% |
| 5.1 GHz | 21% |
| 5.2 GHz | 1% |
Some dies are going to have defects in the shaders, etc. that mean they get binned to a 36CU part regardless of performance, but we know that TSMC has really good 7nm yields and that most (80% plus) of the dies AMD will be getting back will be good dies. Depending on the economics how many cards you can expect to sell at a particular price you may still bin some otherwise functional dies just because you've saturated the demand for the highest performance and priced part.
So let's just imagine a hypothetical scenario with Navi 22. I'll just use the same spread as with 10900K since I have nothing else to go off of or a better starting point. It's probably not accurate, but this is just for illustration.
| Clock Speed | Percent of GPUs Capable |
|---|
| 1.8 GHz | 100% |
| 2.1 GHz | 99% |
| 2.4 GHz | 68% |
| 2.7 GHz | 21% |
| 2.85 GHz | 1% |
Suppose you wanted to target 2.7 GHz for your 6700XT. Only 21% of your full dies make that cut, so if you want the 6700 to be a 36 CU part you're actually binning 80% of your dies even though they could otherwise still hit reasonable clock speeds that where your previous intention in the first place. If you had stayed at something like 2.2 GHz, you might only need to bin 10% of those full die chips.
But you can have both. The top 20% of chips, go into a 6700XT at 2.7 GHz. The next 70% go into a 6700 at 2.2 GHz, and the bottom 10% get the worst performing CUs disabled to allow them to clock higher as a 6600-level part. They can obviously choose other points along that curve to get the kinds of numbers that they need based on sales expectations, etc.
The point about bringing up Navi 23 was that since they'll have another die that will top out at 32 CU, they probably don't have as much incentive to bin 80% of their full Navi 22 dies because they need cards with 32 or 36 CU to target the $300 - $375 part of the market.
This does make the pricing a little more interesting. If AMD does have a Navi 22 that equals the 3070 is 1080p and 1440p due to high clock speeds what do you think they charge for it? I can see an argument for $500, but something like $470 seems more likely. They also need to leave room for whatever they'll have at $400 to square off against the 3060 Ti.
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