TDP is whatever you want it to be. The big cores in an A12Z will pull around 4w each. That means an "unchained" A12Z is a ~16W+ CPU. The 4800H is a 45W TDP, but also has 2x the fast CPU cores. And the binned 4800HS is a 35W TDP, still for 8 cores / 16 threads.

So ~2-3x the TDP for 2x the core count and 4x the thread count. Pretty interesting head to head when the Apple dev kits actually show up in people's hands, don't you think?

I'm unconvinced this comparison is very meaningful at all.

First of all, TDP is not the same thing as power consumption - it is a specification for the required performance of the heatsink/fan cooling solution.

For example: a Ryzen 3900X is a 105W TDP chip. Running at full speed on all 12 cores it consumes 146W; about 10W per core and the remainder for the rest of the package.

Secondly, it is entirely typical to run a single-threaded workload at a higher clock frequency (because if that's all you have to do, why not?), and chasing higher clock speeds is disproportionately expensive since it requires higher voltages, and dynamic power in a switching system increases with the square of voltage.

Again, taking the Ryzen 3900X: that's a nominal 3.8GHz processor. Running a single-threaded workload, it will typically boost up to 4.45GHz in testing. At that frequency, that single core is drawing nearly 18W - i.e. 80% more than at the nominal frequency achieved when all cores are busy and no boost headroom is available.

From what I've read about the A12/A13, the voltage/clock curves are particularly skewed at maximum clock speeds - something like 1.1V at 2.49GHz on the A12 and well under 0.8V at 2.3GHz - basically half the power to run at 93% of the clock speed.

There are a lot of unknowns here, but I think there are more reasons for optimism than your analysis suggests.

Not 4W each. Stop saying this.

SPECint2006 is a single-threaded test: https://images.anandtech.com/doci/14892/specint2006-a13.png

That's either 4-5W per core or the uncore in an A13 is hugely power hungry. I'm rather positive it's not an extremely bad uncore, so the only other option here is a 4-5w per core power figure. Which also lines up with the voltage/frequency curve numbers: https://images.anandtech.com/doci/14892/a12-fvcurve.png

If you have data to support a different number I'm all ears, finding power draw figures in this space is rather difficult, but 4-5W per-core aligns with expectations here. A 1W consumption would be unheard of levels of good.

It’s a meaningless comparison. The 4800H could be a 200W chip if it was “unchained”. Peak burst performance is dynamic in modern CPUs, it’s what you can measure in the real world that matters.

Intel TDP doesn’t include the power usage of DRAM and other IO, or the screen, or WiFi or modem (which may have been disabled tbf).

Geekbench 5 multi core scores are roughly 7400 vs 3300. Let’s say for example that the Thunder cores are half the perf of the Lightning ones. So that 3300 score might be roughly the perf you could get from 4 x Lightning instead of 2 x Lightning and 4 x Thunder. 4800H has 8 cores. Getting a bit over 2x the performance.

But that’s at a TDP of 45W (let’s call it 40W to be more generous). 5W for A13 (well, A13 entire device) vs 40W 4800H. That’s 8x the power draw for 2x performance. Am I wrong?

The linked Anandtech data shows it using 4-5W in a single thread test. That doesn't mean it will use 4-5W/core in a multithreaded test, but thats almost certainly only due to limitations in power delivery and thermals.

With twice the cores at a higher per-core speed, yes. And also with a much more powerful GPU.

Yeah probably 3-4x the TDP (35-54W) with double the threads, 1.8GHz faster per core clock speed and a relatively powerful on-board graphics unit.