• Is it true that every machine that has an Intel CPU is an x86 machine ?

• Considering that all Intel CPU are backward compatible does it mean that every x86 machine is able to run intel CPUs instructions set ?

CodePudding user response：

Is it true that every machine that has an Intel CPU is an x86 machine ?

No! Although nowadays the only Intel CPUs you can buy are x86(-64), historically Intel has produced CPUs in various different architectures like Itanium, i860, i960, iAPX 432, ARM (yes, Intel produced ARM CPUs)... and even the 4004, 8008, 8080, 8048, 8051, MCS-96... Neither of them are binary compatible with each other, except for a few Itanium CPUs that contain an x86 core inside. There are also research architectures from Intel but you can't buy them

You may even see non-x86 CPUs from Intel in the not-so-distant future, because Intel is one of the biggest members of RISC-V and it's already producing RISC-V CPUs although currently for SiFive and not its own design yet

Considering that all Intel CPU are backward compatible does it mean that every x86 machine is able to run intel CPUs instructions set ?

There are no such things as "Intel CPU instruction set" because as said, there are so many different ISAs from Intel. So it should be read as "Considering that x86 CPUs are backward compatible, all current x86 CPUs can run all 16, 32 and 64-bit x86 instruction sets".

However that may soon (or not) be changed. Intel already announced that it'll remove the CSM module for BIOS compatibility completely so it'll lose the ability to run some 16-bit OSes

CodePudding user response：

Currently I believe so. However, there was the Itanium architecture that was not x86 that Intel had released for a while (currently discontinued).