Is an AMD 6 Core a 'true' Core?

RogerMesenseless · 7 Dec 2013 at 23:53

So I saw this screenshot and it intrigued me to be honest. Prime 95 says this 6300 has 3 Cores and 6 Logical cores. This is new to me and as far as I'm aware, AMD doesn't have any Hyperthreading technology so to speak, so how does this work?

Is it a true 6 Core?

Edit: Bottom right of image

Lunastraza · 7 Dec 2013 at 23:58

The 8 cores read as 4 cores with 8 logical processors in windows, however programs like max and keyshot see them as 8 actual cores it's just the way windows uses them, someone told me why once and i think it was to do with how the cores are set out and this being one of the better ways of using them.

Rooster212 · 8 Dec 2013 at 00:04

It isn't, cores have 2 integer units. AMD "8-core" processors are actually 4 cores with 2 integer units in each I believe.

More information: http://en.wikipedia.org/wiki/Bulldozer_(microarchitecture)

Explosivo · 8 Dec 2013 at 01:56

So, Is something like Phenom II with six True cores better than a cpu with 4 True And 4 Logical?

Sorry i haven't really been following the cpu stuff for a while, so it's not worth upgrading from a phenom II x6 to the new eight core, or it is but not worth it for the price?

kefan77 · 8 Dec 2013 at 02:07

not really. it depends on more factors than just cores and the type of application you use.

if it can't utilize more cores, well...

Panos · 8 Dec 2013 at 09:28

AMD 6-8 cores split in 3 or 4 pairs/blocks of cores. (depends 6 or 8 core).

Each block consists 2 cores with all the cache, 2 integer calcs but they share one floating point calc between them.

The reason is that there are more integer calculations done, that floating point ones.

AMD has no logical cores, or hyper threading like the 4 Core intel ones.
http://hothardware.com/articleimages/item1923/big_slide-1.jpg

Cooper · 8 Dec 2013 at 10:28

As much as I've tried, I can't bring myself to accept that they're 'genuine' 4,6 & 8 core CPU's, just as it doesn't feel right to have a CPU with no level 3 cache like these new Kaveri APU's.

If they'd just originally marketed the FX line as 'proper' 2,3 & 4 core CPU's with their own version of 'Hyper Threading', I'd have been happier...and people may have not been as disappointed with their original performance, because of lower expectations.

I agree it's more a problem of perception than reality, but it's of AMD's own making to tech geeks like me.

Having said that, it wouldn't stop me from buying one...especially as these new AMD powered consoles mean proper multi-threaded coding will now be the norm for the next few years, so performance will only get better.

Panos · 8 Dec 2013 at 11:57

Cooper said:
As much as I've tried, I can't bring myself to accept that they're 'genuine' 4,6 & 8 core CPU's, just as it doesn't feel right to have a CPU with no level 3 cache like these new Kaveri APU's.

If they'd just originally marketed the FX line as 'proper' 2,3 & 4 core CPU's with their own version of 'Hyper Threading', I'd have been happier...and people may have not been as disappointed with their original performance, because of lower expectations.

I agree it's more a problem of perception than reality, but it's of AMD's own making to tech geeks like me.

Having said that, it wouldn't stop me from buying one...especially as these new AMD powered consoles mean proper multi-threaded coding will now be the norm for the next few years, so performance will only get better.

Hyperthreading and two cores block sharing the same floating point module are completely different thing. (probably you didn't saw the image attached above?)

An Intel 4 core (eg 4770/4820) with HT, is just that. a 4 core CPU with 4 integer calcs, 4 floating point calcs etc. Where the HT comes to it, when is using that "free" capacity the cores have when they do a process, to do another process.

If an application manages to put all 4 physical cores to 100% on 4 threads, thats is. You have no more. Hence why BF4 runs as fast if not faster on i5 4670 than a i7 4770. Since all the cores are getting utilised, there is no more capacity to them for the HT to kick.

AMD 6-8 cores, are just that 6-8 cores, coming in 3-4 modules
Each module has 2 computing cores, 2 integer calcs, but 1 floating point calc shared between the 2 cores of the module.

As you see that is different than "virtual" cores the Intel has.

joeyjojo · 9 Dec 2013 at 11:19

Panos said:
If an application manages to put all 4 physical cores to 100% on 4 threads, thats is. You have no more. Hence why BF4 runs as fast if not faster on i5 4670 than a i7 4770. Since all the cores are getting utilised, there is no more capacity to them for the HT to kick.

Pretty accurate. I was watching a webcast from CRAY the other day where the guy said hyperthreading was designed to "smooth over" delays due to other parts of the system (disk I/O, network, etc.), and it usually does this well because it's basically a very lightweight (hardware level) thread manager. However, if the system is running "balls to the wall" there are no other delays to speak of and it just does damage.

Martini1991 · 9 Dec 2013 at 13:05

That's what I originally thought HT was a few years ago, and also that HT would become less relevant as IPC/Efficiency per core increased (And BF3 would support this, showing a difference between an i7 and i5 with Multi-GPU's as the CPU cores aren't 100%)

And there is a difference in BF4 with an i5 and i7 with Multi-GPU's ; Multiplayer.
But then we've got Cinebench which will take your CPU to 100% and it'll show a difference between an i5 and an i7, quite drastically..

RogerMesenseless · 9 Dec 2013 at 16:25

This is interesting! Thanks for the info

biuro74 · 13 Dec 2013 at 12:10

Panos said:
Each module has 2 computing cores, 2 integer calcs, but 1 floating point calc shared between the 2 cores of the module.

It's not precise.
Following the Wiki: "The processing core shares the early pipeline stages (e.g. L1i, fetch, decode), the FPUs, and the L2 cache with the rest of the module".
Second pipeline will be added in Steamroller-B (Kaveri build) core as I remember. Since then core might be called "true core" ;-)

krnsniper · 13 Dec 2013 at 16:04

no it's not.

Panos · 13 Dec 2013 at 18:54

Seems you missed that, I posted before

http://hothardware.com/articleimages/item1923/big_slide-1.jpg

mmj_uk · 13 Dec 2013 at 19:06

I would class a 'true' 8 core processor as having 8 identical/independent cores so I would say no, it's level of performance is consistent with a true quad core so I would say it's more of a hybrid processor. There is no such thing as a 'module' really, it's just what AMD have chosen to call their non-traditonal cores.

Jumper118 · 13 Dec 2013 at 19:29

yes it has 6 cores, they are just rubbish ones!

Jumper118 · 13 Dec 2013 at 19:39

double post ignore

JonJ678 · 15 Dec 2013 at 02:59

Intel & AMD, or at least their marketing departments, disagree about what a core is. That's all.

Rroff · 15 Dec 2013 at 03:07

Panos said:
If an application manages to put all 4 physical cores to 100% on 4 threads, thats is. You have no more. Hence why BF4 runs as fast if not faster on i5 4670 than a i7 4770. Since all the cores are getting utilised, there is no more capacity to them for the HT to kick.

I have a very different experience with regard to BF4 and 4 core / 4 thread v 4 core / 8 thread. While performance (as in the reported FPS numbers) remains approx similiar with HT on or off the game is a stuttery mess with it off (whereas a lot of people report the opposite effect with BF3 - that its smoother with HT off).

IMO the game has been opptimised to run over 8x lower powered AMD cores and hence HT gets used better than traditionally on high end intels.

CAT-THE-FIFTH · 15 Dec 2013 at 04:49

Technically the integer cores were consider the traditional cores and the FPU as a separate co-processor in older CPUs.

The FX6300 has six integer cores and three floating point units,so it is a six core CPU. However,the cores are quite "narrow" in comparison to what Intel uses.