It sure does. Some is inherent to the ISA itself. And some undefined behavior is errata that differs from CPU to CPU. Check out the errata documentation for a

It sure does. Some is inherent to the ISA itself. And some undefined behavior is errata that differs from CPU to CPU. Check out the errata documentation for any processor released in the last few decades. For example, x86. You can trigger things that happen on one x86 CPU that won't happen on another.