A laptop (or desktop!) computer has a significantly higher energy budget than the iPad. The SoC Apple uses in those devices could conceivably be clocked higher and/or have more cores than the A12 parts they're currently using in the iPad Pro.

Well, it entirely depends on how they designed the chip. If they planned ahead they could design the chip for 4Ghz ahead of schedule and then take advantage of the higher frequency once they decide to actually release a desktop or laptop with an ARM chip. I don't believe that Apple did this so they will either create a new chip exclusively for desktop/laptop or they just keep the low frequency.

> You can't exactly just shove a turbo on an under-powerd commuter I4 engine (fuel efficient) and expect it to turn out well.

Isn’t this the exact concept of the VAG EA888 motor used in the Audi A4 and extended all the way up to the S3?

That said, the rumored chip is an actively cooled 12 core 5nm part which is more like an RS3 motor with extra cores/ cylinders

Way different thermal envelope? iPads are passively cooled.

Isn't that a selling point of ARM? Would you prefer a passively cooled but only slightly slower laptop or a faster laptop with a noisy fan?

I don't think there can be a universally accepted answer to this, as there are so many different user priorities for laptops.

Having said that, I think the top requirement for most laptops is that "it's gotta run what I need it to run on day one".

For a huge amount of light users, ARM Macs are going to satisfy that requirement easily.

Once you move up the food chain to users with more complicated requirements, however, it's less of a slam dunk... for the moment.

That's because neither does build even a top tier mobile ARM chip. Each of their best offerings is about half as fast as Apple's A12X/Z

Because with the A series they show that they know how to make a good CPU that fits into the thermal restrictions of the chassis.