Here are a few:
- > 26 bit address space
- multiplication in hardware
- more complex instructions
- backwards compatibility with the 80286
- on-chip MMU
- support for a FPU
> that justify an order of magnitude?
I wouldn’t know. Backwards compatibility certainly is high on the list because, when it was released, many users had fairly high investments in commercial software.
Of course, SSE/NEON was decades in the future.
As we note, Intel did not value backwards compatibility at the outset of the i386.
Perhaps an Acorn acquisition and the sudden ownership of a low-power CPU that they could make for peanuts might have also had a profound impact.
It would have been interesting to see Intel making BBC Micros.
With the 8086, sure. v86 got you covered.
With 80286? Not really. It might have some of the instructions, but it does not support 286's protected mode.
Here are a few:
- > 26 bit address space
- multiplication in hardware
- more complex instructions
- backwards compatibility with the 80286
- on-chip MMU
- support for a FPU
> that justify an order of magnitude?
I wouldn’t know. Backwards compatibility certainly is high on the list because, when it was released, many users had fairly high investments in commercial software.