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by qayxc 1750 days ago
> Finally, again, 15W TDP is not the same as 15W under normal usage. That misunderstanding appears to be driving most of your disagreements in this thread.

No. The CPUs can be configured to consume no more than 15 Watts, even if few OEMs do so. Same goes for the M1 - there's no difference with regards to this: both the MBP 13 and the Mac Mini have higher power limits and active cooling for that reason.

In fact, the latest U-series mobile Ryzen CPUs are even optimised to be most efficient at a 15W power level, contrary to Intel's Ice Lake chips, which get the most performance at a higher wattage configuration of 28 Watts.

1 comments

Again, as a number of people corrected you, it's not a simple 15W figure but specifically the listed maximum 15W thermal design power (TDP).

That's a term in the industry with a specific meaning:

https://en.wikipedia.org/wiki/Thermal_design_power

The key thing to understand is that this is not measured power consumption while running the benchmarks and you cannot reliably compare the values even across the same product line, much less across chips — especially when we're talking about SoC designs where, for example, the TDP refers to the entire chip but the benchmarks being discussed are all CPU-focused and don't even exercise the GPU at all. We also know that TDP numbers are not a hard ceiling: there are some chips which under some conditions — most commonly but not always synthetic benchmarks — will exceed those figures, possibly by somewhat significant margins.

OK. For the last time, here's a freakin' screenhot to illustrate the point: https://ibb.co/QYnj40r

What you see there is are the power limits of the CPU (as reported by HWInfo64).

If you set the POWER LIMIT in the UEFI/BIOS, this regulates THE POWER consumption of the chip. NOTHING to do with TDP.

Why is that so hard to grasp for you? You can even measure the power rom the wall to confirm this. I am NOT talking about TDP here!