Jon Stokes's Inside the Machine covers this topic (and others) in some detail. I'm not all that familiar with the guts of VIA's designs. You can now stay updated with Mac’s CPU temp and fan speed. As a free benchmarking app available in the Mac App Store, Novabench will test your Mac CPUs integer arithmetic speed, perform a general CPU test. This will add the Fanny Widget in the main bar. From the list, Select Fanny by clicking the ‘+’ icon against it. In theory, they could be adapted to emulate any instruction set. In your Mac’s notification bar, click Today followed by clicking 1 New at the bottom.

Transmeta's Crusoe products were widely noted for using a (fairly complicated) emulation system that allowed them to translate x86 instructions into their own internal RISC language. The Core microarchitecture (Core 2 Duo, Core 2 Quad, etc.) took this a step further by introducing Macro-Ops Fusion, a method of 'fusing' certain x86 instructions together for faster execution (an extension of the concept of Micro-Ops Fusion, introduced with the Pentium M, that does the same for micro-ops). Intel's Pentium Pro ('P6') did the same thing, as did the products based on it (Pentium II, Pentium III, etc.) and those that came later.

All of AMD's subsequent designs used a similar approach. Click to expand.AMD's K5 was a RISC core that translated x86 instructions into its own internal instructions (what are today called 'micro-ops').

Mac cpu speed diagnostics