But you’re trying to estimate the power needed to attain that score and instead you got hung up on a fixed GHz and then decided it was not plausible because such a score required too much IPC uplift to be plausible....
That’s what I’m trying to say you’re effectively missing a factor in your calculations that lead you to the wrong conclusion that the IPC uplift is unlikely - which 31% would be!
Nope, I didn't get hung up on a fixed GHz (inded, you'll see from the quote below that it's exactly the opposite), nor did I miss a factor, nor did I conclude IPC uplift is unlikely. It seems you've managed to misinterpret a large fraction of what I wrote.
Again, I choose 4.2 GHz as a target, and intially said you'd need an additional 30% from IPC + process to get to the 3986 score. But then I added a correction saying you wouldn't have IPC + process, you'd only have IPC, because process is subsumed into IPC and clock (initially you argued the point with me but finally agreed).
EDIT: Upon further consideration, an ~30% generational increase in IPC may be unlikely. But that just means that, if this result is real, Apple was experimenting with even higher clocks than 4.2 GHz.
[Emphasis added] I.e., I realized that, since a 30% IPC uplift was unlikely, you'd probably need a bit more than 4.2 GHz to reach the target score. Do I really have to get into parsing English with you to explain that acknowleding you'd need higher clocks is the opposite
of getting "hung up on a fixed GHz"?? Further, in no way did I say that such was implausible. I've no idea where you're getting that from.
Indeed, I'd considered redoing my calculation with higher clocks and a lower IPC, but it didn't seem worth it, since this whole thing was such a rough estimate anyways. After all, I'm not even sure what the exponent is supposed to be.
Either way, I figured my conclusion stands: By limiting the higher clock (whatever it is) to 2–4 cores, and possibly adding an algorithm that limits their use to when the GPU isn't being stressed then, based on my rough upper bound calculation, you can probably deal with the added TDP in Macs besides the MP (Studio, Mini, 16" MBP) (in the MP you'd of course be even less constrained).
Nor was I missing a factor for efficiency improvment due to the M3's (expected) improved N3 process, since that was already subsumed into my starting point, which was what the M3's
WPC would be at 3.66 GHz:
Suppose that the M3 P-cores consume 5 WPC (watts per core) when running at 3.66 GHz
Yes, I could have done a more detailed calculation that started with the M2 and the tried to add an efficiency improvement for going from M2 and M3. But I didn't want to. It was simpler to just start with an estimate for the M3's TDP, and proceed from there. You say this:
I know what Fermi calculation means.
...but you don't seem to appreciate its spirit. The point is to do a very rough, simple calculation, requiring as little input as possible. That's what I did, and yet you're quibbling with me about small details that are not needed for a very coarse-grained analysis. You seem to think I missed something—got things wrong—because I didn't include those details. No. Excluding those details was a choice. I feel like I'm back at MacRumors!