Intel's Core Ultra 2 Chip Posts Nearly 24-Hour Battery Life in Lunar Lake (opens in new tab)

Loading up powertop on my i7 6600u reports an idle draw of 5.5w with my browser open playing music. I think that's pretty damn good, for an old-ish laptop with mitigations enabled on Linux.

This is actually a bad example because C style decls are provably, objectively, bad. They make parsing harder and once the types are non-trivial, they are absurdly hard to read and write. The case in point being non-trivial function pointers in C. The syntax for declaring a function pointer of a type that returns a function pointer is hidious.

Meanwhile here is how you define a function in that returns a function that returns a string in a modern language (Typescript):

    type NumberToStringFunction = (num: number) => () => string;

    typedef char* (*(*NumberToStringFunction)(int))(void);

It is very easy to add CPU features that place a hard limit on performance. That is why Arm64 dropped all the conditional stuff! (Any instruction that limits the potential branch prediction is going to severely impact potential CPU performance.) History is littered with failed CPU architectures that just couldn't scale up, Intel's famous folly being Itanium.

That said, x86 is mature and it dropped some of its less pleasant aspects with x64.

Also IMHO drivers matter more for laptops than the CPU does. A bad driver keeping the GPU on w/o need or just not being able to enter the lower sleep states in general, will kill battery faster than anything else.

Language syntax does affect the speed of the parser

The bigger deal about the M-series performance and efficiency is SoC, not the ISA. This is something that could take off in the x86 world though it stifles upgradeability

Cinebench R24 ST[0]:

* M3: 12.7 points/watt, 141 score

* X Elite: 9.3 points/watt, 123 score

* Intel Ultra 7 258V (new): 5.36 points/watt, 120 score

* AMD HX 370: 3.74 points/watt, 116 score

* AMD 8845HS: 3.1 points/watt, 102 score

* Intel 155H: 3.1 points/watt, 102 score

Cinebench R24 MT[0]:

* M3: 28.3 points/watt, 598 score

* X Elite: 22.6 points/watt, 1033 score

* AMD HX 370: 19.7 points/watt, 1213 score

* Intel Ultra 7 258V (new): 17.7 points/watt, 602 score

* AMD 8845HS: 14.8 points/watt, 912 score

* Intel 155H: 14.5 points/watt, 752 score

PCMark did a battery life comparison using identical Dell XPS 13s[1]:

* X Elite: 1,168 minutes, performance of 204,333 in Procyon Office

* Intel Ultra 7 256V (new): 1,253 minutes, performance of 123,000 in Procyon Office

* Meteor Lake 155H: 956 minutes, performance of 129,000 in Procyon Office

Basically, Intel's new chip has 7% more battery life than X Elite but the X Elite is 66% faster while on battery. In other words, Intel's new chip throttles heavily to get that battery life.

  >Of course they ignored things like node advantage, but who cares? ;)

  >Where are all those people who for years (or since M1) were claiming that x86 is dead because ARM ISA (magically) offers significantly better energy-efficiency than x86 ISA.

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[0]Data for M3, X Elite, AMD, Meteor Lake taken from the best scores available here: https://www.notebookcheck.net/AMD-Zen-5-Strix-Point-CPU-anal...

[0]Data for Core Ultra 7 taken from here: https://www.notebookcheck.net/Asus-Zenbook-S-14-UX5406-lapto...

[1]https://youtu.be/QB1u4mjpBQI?si=0Wyf-sohY9ZytQYK&t=2648