Can you expand upon this please?
What is it about the demo itself that tells you that they were running high frequencies, and that this necessitates lower clocks on a 16c SKU?
I'm seeing an ES sample that would have been running high voltages for stability, and not necessarily high clocks. In fact, anything 4.5GHz+ would represent IPC regression, which is highly unlikely.
Beyond that, we know that IF consumes huge chunks of power, and if we model that to the actual power usage for the demo, we can see that the 8c chiplet is likely not consuming much power at all. In fact, another 8c chiplet is unlikely to add more than 20-30w at the same frequency as in the demo. The 16c SKUs are supposedly 125w and 135w.
I'm fairly confident that AMD were sandbagging. Perhaps not by a massive amount, but by enough to get the message across.
See the anandtech article that TDP range will remain the same as ryzen2. So no 125-135w SKUs.
The 4.5 Ghz statement from sources wouldn't be a CB15 regression. The 2700x gets 1750 at 4.3 so it'd still be a 12% IPC improvement. Based upon statements in this thread from a few posters the changes to the FPU wouldn't have much of an impact on CB15 anyway so average IPC uplift would still be higher.