Hacker News Reader

Comment by hajile | Hacker News Reader

M1 is barely 20-25w at the wall. Actual chip peak TDP is more like 14-18w. (EDIT: this is measured from a Mac mini by Anandtech -- a laptop likely has slightly lower TDP due to better binning)

Intel chips have much higher peak and sustained actual power usage than their TDP indicates. At the wall, those “15w” systems are actually much closer to 40-60w on sustained loads.

View on HN

> At the wall, those “15w” systems are actually much closer to 40-60w on sustained loads.

They dont. PL2 only last at best 30 secs. Not Sustained Loads. Laptop depending on heatsink config sustain at either 15W at base clock or 28W at slightly higher clock.

The M1 Mac mini under full load is 39W as an official Apple Published Figure [1].

Not sure why people are downvoting my original post. But I guess that is the state we are in for hardware topic on HN.

[1] https://support.apple.com/en-us/HT201897

Correct me if I'm wrong, but isn't this conflating CPU TDP and overall system consumption? When a system is under maximum sustained load, power consumption increases are not limited to the CPU or SoC. I suspect the figures published by Apple (6.8W and 39W) represent the absolute theoretical extremes possible by the system, not typical numbers for real-world idle and load.

I believe benchmarked numbers more than official statements.

https://www.anandtech.com/show/16252/mac-mini-apple-m1-teste...

For comparison, Panther Lake 1165G7 NUC uses as much as 85w (70w sustained) when maxing out its load. The author even notes how they'd beefed up the cooling.

https://nucblog.net/2021/02/panther-canyon-i7-nuc-review-nuc...

It’s very hard to estimate the true power consumption of laptops since they are all primarily fed from the battery not the charger. There are almost no passthroughs anymore even in “gaming” laptops. Only a handful of DTR laptops still employ a passthrough with a high wattage PSU or dual PSU set up and I honestly haven’t seen those for the last 2-3 gens...

The last one I’ve seen that had it was a 8700K with dual 1080’s DRT monstrosity.

> It’s very hard to estimate the true power consumption of laptops since they are all primarily fed from the battery not the charger.

That's news to me. I try to keep up to date with laptops, and all the reviewers have pretty accurate power consumption measurements. Even just using the internal reporting reveals quite a few details [1].

Even a "12W" TDP 11th gen Intel CPU can draw up to 50W in turbo mode [2].

The 11th gen "45W" laptop CPUs have a PL2 power draw of 135W [3], which, thermals and VRMs permitting, can be held indefinitely according to the specs (which is what makes Intel's whole TDP-rating useless indeed).

So yes, it's very hard indeed to estimate newer laptop's power consumption, but for entirely different reasons. It's primarily the cooling and OEM's choice of how to implement the very loosely defined (Intel!-) specs that define power draw. If you have excellent cooling, there's nothing to stop an 11800H from drawing 135W for minutes at a time... (which can be measured, both internally and from the wall no problem).

AMD CPUs on the other hand mostly adhere to the published power rating (give or take 20% - again, cooling permitting and configurable by the OEM).

[1] random example: https://bit.ly/34xLKpM

[2] https://www.anandtech.com/show/16084/intel-tiger-lake-review...

[3] https://www.itworldcanada.com/article/eight-core-intel-tiger...

I've never seen a laptop with a removable battery where you couldn't remove the battery and power it directly.

Reply on news.ycombinator.com