Originally Posted by azanimefan
Answer to come, first I'll address the two wrong answers to this question you've received so far.
Wrong/incomplete- or at least this answer doesn't address the charge that a 8 core fx cpu isn't an 8 core cpu. What they do with the kavari apu however... i address next.
ah... yeah... AMD deserves some flack for the APU - 12 core thing. As much flack as Intel deserved (and got) for claiming in 2005 that hyperthreaded P4s were dual core cpus. But the APU thing and the Piledriver 8 core thing are totally separate issues completely. That said, AMD is clearly trying to rebuild the whole concept of the cpu with the Kavari APU; so i get where they're going but it's still as stupid as those original hyperthreading commercials (at least they aren't doing a national TV ad campaign claiming it's a 12 core... that would really be embarrassing).
Now then, onto the topic of the bulldozer cpu architecture. Some intel fanboys like to make the claim its a type of "hyperthreading" and not a true "8/6/4" core cpu. I suppose i can sorta see their point of view but like most fanboy arguments it's based on a lack of understanding or just pure sophistry.
The engineering definition of a cpu "core" is that a core must have 3 parts
1) instruction control unit
2) instruction execution unit
3) input/ouput unit
AMD's bulldozer family cpu cores have all of these parts; each core module contains 2 separate cores, each one of those cores has their their own scheduler (control unit), 4 execution units, and an I/O unit.
The confusion about the bulldozer architecture, comes from the floating point processor unit. You see up until 2000 or so, no cpu had a floating point processor. In fact computers around 1997 started to include math-coprocessors add on boards to handle the floating point math... around 2000 cpus started to integrate the math coprocessor, called a floating point processor onto the cpu itself. These units basically handle floating point math (calculus) which traditional cpus rather suck at. Now understand, these floating point processors are completely separate units from the cpu core on both an AMD and Intel cpu... in a way they're sorta the progenitor to the whole concept of an APU, as all a gpu really is, is a highly specialized math coprocessor or calculus calculator. AMD chose, with bulldozer, to place 1 256-bit floating point processors on their cpu per core module... that single FPU is naturally a 256-bit unit, but when needed can function like 2 128 bit FPUs, THIS is the part that works like a gimped version of intel's hyperthreading; as in it's a single FPU which can at times, when needed handle 2 instructions at the same time.
The fx cpus ARE by every
definition proper 4/6/8 core cpus. They just work a little different with their design then an intel cpu... or even the older retired AMD k10 architecture; with bulldozer AMD went modular, it's intention was to make a chip they could easily customize for server environments, and any other "unique" environments they may be requested by a client to match. Its actually because of the highly modular design of bulldozer that AMD landed the 2 next gen consoles... it simply was cheaper and easier to make a custom chip for both M$ and Sony then it was for anyone else to do. Its also because of this modular and unfocused design that bulldozer/piledriver/steamroller simply can't compete in performance with intel's highly specialized performance cpu lines.