AMD FX 8350 being detected as a 4 core CPU

EpiclyDelicious said:

The FX-8350 isn't a technically an eight-core processor. It is, but not in the sense that you think. It's four real cores with 1 "virtual" core on each real core I believe. I'm not good at explaining it, but that's the best explanation of what I know, or think.

This is why the FX-8350 isn't too good at single-core performance.

Quote:

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.

ingtar33 said:

EpiclyDelicious said:

The FX-8350 isn't a technically an eight-core processor. It is, but not in the sense that you think. It's four real cores with 1 "virtual" core on each real core I believe. I'm not good at explaining it, but that's the best explanation of what I know, or think.

This is why the FX-8350 isn't too good at single-core performance.

This post is completely 100% wrong.

I'm going to copy and paste my own post on another forum explaining this one more time...

Quote:

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.

ingtar33 said:

Sorry, I did not mean to say you were a fanboy. As I stated in my post I was quoting from a separate forum post, the discussion at the time had a number of fanboys arguing at the time saying silly stuff. I probably should have edited out the comments about fanboys but I was distracted and in a rush.

As to the claim there is no definition of a CPU core. That is also wrong. I just gave you the engineering definition. Yes the share resources, that's part of the modular design. It's a good design it just suffers from a lot of power 'bleed', as a result it simply doesn't scale in performance well.

vmN said:

Do you have any kind of validation that that is engineering definition of a core?

Also I wouldn't really call an ALU an core, as you mentioned.

Piledriver simply suffer, because of the execution unit per core is low compared to Intels.

Haswell have 4 ALUs per core whereof Piledriver have 4 ALUs per module (2 ALUs for each "core").
And not even to mention SIMD...

EpiclyDelicious said:

The FX-8350 isn't a technically an eight-core processor. It is, but not in the sense that you think. It's four real cores with 1 "virtual" core on each real core I believe. I'm not good at explaining it, but that's the best explanation of what I know, or think.

This is why the FX-8350 isn't too good at single-core performance.