i386, i686

[Deleted member 143938]

What do these mean? For example when downloading a Linux distro some come in i386 variants, others in i686.. I know it has something to do with the CPU but I'm not sure what.

I quickly read in Wiki that it's called a microarchitecture and that all it means is how the circuits are arranged in the CPU, but that doesn't really make sense in this context.

Does i686 provide greater speeds than i386?

Can an i686 run an i386 OS?

What's Vista? i686 I assume?

 

[Elledan]

i386 is all 32-bit x86 chips from the Pentium I and lower (486, 386).
i586 is the Pentium Pro architecture.
i686 started with the PII and is still the current architecture.

Basically each revision adds/changes a few instructions, making it incompatible with a previous revision. i386 generally runs on newer revisions, though.

i686 may provide some more efficient instructions for certain tasks and therefore be faster, although these chips will generally have SSE2/3 and such as well. Vista is most likely compiled for i686, yes, though it's hard to find out such information