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Comment by skohan | Hacker News Reader

Is there a tradeoff in terms of power consumption?

Yes. But the 14" and 16" has larger battery than 13" MacBook Pro or Air. And they were designed for performance, so two less EE core doesn't matter as much.

It is also important to note, despite the name with M1, we dont know if the CPU core are the same as the one used in M1 / A14. Or did they used A15 design where the energy efficient core had significant improvement. Since the Video Decoder used in M1 Pro and Max seems to be from A15, the LPDDR5 is also a new memory controller.

In A15, Anandtech claims the Efficiency cores are 1/3 the performance, but 1/10 the power. They should be looking at (effectively) doubling the power consumption over M1 with just the CPUs and assuming they don't increase clockspeeds.

Going from 8 to 16 or 32 GPU cores is another massive power increase.

I wonder if Apple will give us a 'long-haul' mode where the system is locked to only the energy efficient cores and settings. I us developer types would love a computer that survives 24 hours on battery.

macOS Monterey coming out on the 25th has a new Low Power Mode feature that may do just that. That said, these Macs are incredibly efficient for light use, you may already get 24 hrs of battery life with your workload. Not counting screen off time.

Yes, it depends on what you're doing, but if you can watch 21 hours of video, many people will be able to do more than 24 hours of development.

Video playback is accelerated by essentially custom ASIC processing built into the CPU, so it's one of the most efficient things you can do now. Most development workloads are far more compute intensive.

I get about 14-16 hours out of my M1 MacBook Air doing basically full-time development (browser, mail client, Slack, text editor & terminal open, and compiling code periodically).

I know everyone's use case is different, but most of my development workload is 65% typing code into a text editor and 35% running it. I'm not continually pegging the CPU, just intermittently, in which case the existence of low power cores help a lot. The supposed javascript acceleration in the M1 has seemed to really speed up my workloads too.

Might be less computationally expensive. But video playback constantly refreshes screen which uses up battery

Did Electron fix the 60Hz (or rather current screen refresh rate) cursor blinking? Otherwise I don't see many web devs getting a lot of runtime in.

That's actually a curious question, I wonder what the most energy efficient dev tool is. Can't imagine its VScode. Maybe plain terminal with VIM?

This is true, but it's not worst case by far. Most video is 24 or 30 fps, so about half the typical 60 hz refresh rate. Still a nice optimization path for video. I'm not sure what effect typing in an editor will have on screen refresh, but if the Electron issue is any indication, it's probably complicated.

Huge, apparently. I just spent a bit over $7,000 for a top-spec model and was surprised to read that it comes with a 140 watt power adapter.

Prior to my current M1 MBP, my daily driver was a maxed-out 16" MBP. It's a solid computer, but it functions just as well as a space heater.

And its power adapter is only 100 watts.

the power supply is for charging the battery faster. the new magsafe 3 system can charge with more wattage than usb-c, as per the announcement. usb-c max wattage is 100 watts, which was the previous limiting factor for battery charge.

USB Power Delivery 3.1 goes up to 240 W (or, I should say, “will go up” as I don’t think anybody is shipping it yet)

USB-C 3.1 PD delivers up to 240watts.

That's with 2 connectors right? I have a Dell Precision 3760 and the one connector charging mode is limited to around 90W. With two connectors working in tandem (they snap together), it's 180W.

The connectors never get remotely warm .. in fact under max charge rate they're consistently cool to touch, so I've always thought that it could probably be increased a little bit with no negative consequences.

Single connector, the 3.1 spec goes up to 5A at 48V. You need new cables with support for the higher voltages, but your "multiple plugs for more power" laptop is exactly the sort of device it's designed for.

It was announced earlier this year, so not in wide use yet. PDF warning: https://usb.org/sites/default/files/2021-05/USB%20PG%20USB%2...

I’ve not seen any manufacturer even announce they were going to make a supported cable yet, let alone seen one that does. I might’ve missed it though. This will only make the hell of USB-C cabling worse imho.

The USB Implementers Forum announced a new set of cable markings for USB 4 certified cables that will combine information on the maximum supported data rate and maximum power delivery for a given cable.

Currently I think there aren't any, and the MBP will only get its full 140W capacity using the magsafe cable.

Color me skeptical.

I believe you (and Apple) that the battery can be charged faster, but I am currently rendering video on an M1 MBP. Its power draw: ~20 Watts.

That's a lot of charging overhead.

The 16” has a 100wh battery, so it needs 100w of power to charge 50% in 30 minutes (their “fast charging”). Add in 20w to keep the laptop running at the same time, and some conversion losses, and a 140w charger sounds just about right.

That actually sounds on the money. I hope you're right!

The other end of the new MagSafe is usb-c, which gets plugged into the power adapter.

Sure, but it's an Apple cable plugging into an Apple socket. They don't have to be constrained by the USB-C specs and could implement a custom high power charging mode. In fact I believe some other laptop manufacturers already do this.

They support fast-charging the battery to 50% in 30 minutes. That's probably the reason for the beefy charger.

I'm surprised the fast charger isn't a separate purchase, a la iPhone.

I’m not particularly surprised. They have little to prove with the iPhone, but have every reason to make every measurable factor of these new Macs better than both the previous iteration and the competition. Throwing in a future-model-upsell is negligible compared to mixed reviews about Magsafe 3 cluttering up reviews they otherwise expect to be positive.

Yeah I'd prefer that. Converted everything to quality 6ft braided usb-c cables, bought a separate multiport charger. Will have to sell original one...

Just in case people missed it - the magsafe cable connects to the power supply via usb-c. So (in theory) there's nothing special about the charger that you couldn't do with a 3rd party charger, or a multiport charger or something like that.

MagSafe was a gimmick for me - disconnects far too easy, cables fray in like 9 months, only one side, proprietary and overpriced. Use longer cables and they will never be yanked again. MBP is heavy enough that even USB-C is getting pulled out on a good yank.

I briefly had an M1 Macbook Air and the thing I hated the most about it was the lack of Magsafe. I returned it (needed more RAM) and was overjoyed they brought Magsafe back with these and am looking forward to having it on my new 16" You can also still charge through USB C if you don't care for Magsafe.

Might be a power limitation. I have an XPS 17 which only runs at full performance and charges the battery with the supplied 130W charger. USB C is only specced to 100W. I can still do most things on the spare USB C charger I have.

With the latest USB-PD standard that was announced in May, up to 240W is supported

I have a top-spec 15” MBP that was the last release just before 16”. It has 100W supply and it’s easy to have total draw more than that (so pulling from the battery while plugged in) while running heavy things like 3D games. I’ve seen around 140W peak. So a 150W supply seems prudent.

In the power/performance curves provided by Apple, they imply that the Pro/Max provides the same level of performance at a slightly lower power consumption than the original M1.

But at the same time, Apple isn't providing any hard data or explaining their methodology. I dunno how much we should be reading into the graphs. /shrug

I think you misread the graph. https://www.apple.com/newsroom/images/product/mac/standard/A...

The graph there shows that the new chip is higher power usage at all performance levels.

Not all; it looks like the M1 running full-tilt is slightly less efficient for the same perf than the M1 Pro/Max. (I.e., the curves intersect.)

Yes, but only at the very extreme. It's normal that a high core count part at low clocks has higher efficiency (perf/power) at a given performance level than a low core count part at high clocks, since power grows super-linearly with clock speed (decreasing efficiency). But notably they've tuned the clock/power regime of the M1 Pro/Max CPUs that the crossover region here is very small.

I think this is pretty easy to math: M1 has 2x the efficiency cores of these new models. Those cores do a lot of work in measured workloads that will sometimes be scheduled on performance cores instead. The relative performance and efficiency lines up pretty well if you assume that a given benchmark is utilizing all cores.

> M1 Pro delivers up to 1.7x more CPU performance at the same power level and achieves the PC chip’s peak performance using up to 70 percent less power

Uses less power

That's compared to the PC chips, not M1. M1 uses less power at same performance levels.

https://www.apple.com/newsroom/images/product/mac/standard/A...

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