The M series chips aren’t the absolute fastest in raw speed, though they are toward the top of the list, but they destroy x86 lineage chips on performance per watt.

I have an M1 Max, a few revisions old, and the only thing I can do to spin up the fans is run local LLMs or play Minecraft with the kids on a giant ultra wide monitor at full frame rate. Giant Rust builds and similar will barely turn on the fan. Normal stuff like browsing and using apps doesn’t even get it warm.

I’ve read people here and there arguing that instruction sets don’t matter, that it’s all the same past the decoder anyway. I don’t buy it. The superior energy efficiency of ARM chips is so obvious I find it impossible to believe it’s not due to the ISA since not much else is that different and now they’re often made on the same TSMC fabs.

> they destroy x86 lineage chips on performance per watt.

This isn't really true. On the same process node the difference is negligible. It's just that Intel's process in particular has efficiency problems and Apple buys out the early capacity for TSMC's new process nodes. Then when you compare e.g. the first chips to use 3nm to existing chips which are still using 4 or 5nm, the newer process has somewhat better efficiency. But even then the difference isn't very large.

And the processors made on the same node often make for inconvenient comparisons, e.g. the M4 uses TSMC N3E but the only x86 processor currently using that is Epyc. And then you're obviously not comparing like with like, but as a ballpark estimate, the M4 Pro has a TDP of ~3.2W/core whereas Epyc 9845 is ~2.4W/core. The M4 can mitigate this by having somewhat better performance per core but this is nothing like an unambiguous victory for Apple; it's basically a tie.

> I have an M1 Max, a few revisions old, and the only thing I can do to spin up the fans is run local LLMs or play Minecraft with the kids on a giant ultra wide monitor at full frame rate. Giant Rust builds and similar will barely turn on the fan. Normal stuff like browsing and using apps doesn’t even get it warm.

One of the reasons for this is that Apple has always been willing to run components right up to their temperature spec before turning on the fan. And then even though that's technically in spec, it's right on the line, which is bad for longevity.

In consumer devices it usually doesn't matter because most people rarely put any real load on their machines anyway, but it's something to be aware of if you actually intend to, e.g. there used to be a Mac Mini Server product and then people would put significant load on them and then they would eat the internal hard drives because the fan controller was tuned for acoustics over operating temperature.

> I have an M1 Max, a few revisions old, and the only thing I can do to spin up the fans is run local LLMs or play Minecraft with the kids on a giant ultra wide monitor at full frame rate. Giant Rust builds and similar will barely turn on the fan. Normal stuff like browsing and using apps doesn’t even get it warm.

This anecdote perfectly describes my few generation old Intel laptop too. The fans turn on maybe once a month. I dont think its as power efficient as an M-series Apple CPU, but total system power is definitely under 10W during normal usage (including screen, wifi, etc).

I'd rather it spin the fan all the time to improve longevity but that's just me.

One of the many reasons why snapdragon windows laptops failed was both amd and Intel (lunar lake) was able to reach the claimed efficiency of those chips. I still think modern x86 can match arm ones in efficiency if someone bothered to tune the os and scheduler for most common activities. M series was based on their phone chips which were designed from the ground up to run on a battery all these years. AMD/Intel just don't see an incentive to do that nor do Microsoft.

Afaik they are the fastest cores in raw speed. They’re just not available in very high core offerings so eventually fall behind when parallelism wins.