is "8 core" BD really a quad core?

ChronoBodi · Oct 17, 2011

there's all the media talk of "OMG 8 core loses to intel 4 core!"

I think that's not really correct, should it be 4 modules vs 4 cores? But then again they look at the Bulldozer and are like "WOAH 8 cores!"

WizrdSleevz · Oct 17, 2011

There 2 cores for ever module so yes.. it is a 8 core CPU.

The_Hairy_Yak · Oct 17, 2011

BD is a real 8 core cpu, SB is a 4 core CPU with hyper-threading for a "theoretical" 8 core CPU. However the architecture for SB is superior, so SB quad+ht > BD octo

thrasherht · Oct 17, 2011

The key part that makes up a core is the actual processing unit inside the core, so since each module has two FPUs in it, that is 2 cores. So yes, 8 cores.

ChronoBodi · Oct 17, 2011

ah, i was confused, because the benchies shows the SB beating the Bulldozer quite badly... which makes me think, should they improve single-thread performance by running one thread per module?

Transhour · Oct 17, 2011

Quote:

Originally Posted by ChronoBodi

there's all the media talk of "OMG 8 core loses to intel 4 core!"

I think that's not really correct, should it be 4 modules vs 4 cores? But then again they look at the Bulldozer and are like "WOAH 8 cores!"

define "core" please...we say things that have no real meanings, like we call most modern cpu's 64bit, but they aren't really, there plenty of parts that have more bits and less bits than that. they have 64 bit gprs, but 128-bit xmm registers, but the memory registers are 48 bit, and most fpu's are 128 bit...so why do we think of them only as 64 bit cpu's?

so to answer your questions, you'd have to answer what makes a core.

ChronoBodi · Oct 17, 2011

yea that's the problem, it used to be that a "core" means the Intel and older AMD models.

However, the bulldozer changes this quite a bit, so, a single definition of "core" doesn't apply to all chips.

Malcolm · Oct 17, 2011

CPU-Z shows 8 cores/8 threads, so I would assume it's 8 "real" cores?

Dman · Oct 17, 2011

Quote:

Originally Posted by ChronoBodi

there's all the media talk of "OMG 8 core loses to intel 4 core!"

I think that's not really correct, should it be 4 modules vs 4 cores? But then again they look at the Bulldozer and are like "WOAH 8 cores!"

Who cares, it doesn't work how it's suppose to, and that's all that really matters in the end, isn't it?

Transhour · Oct 17, 2011

Quote:

Originally Posted by ChronoBodi

yea that's the problem, it used to be that a "core" means the Intel and older AMD models.

However, the bulldozer changes this quite a bit, so, a single definition of "core" doesn't apply to all chips.

well it never really has

, they add and remove stuff all the time. amd just did it in a grand swoop.

jackbrennan2008 · Oct 17, 2011

Quote:

Originally Posted by Malcolm

CPU-Z shows 8 cores/8 threads, so I would assume it's 8 "real" cores?

It's a moduled design where you have 4 modules in the 8150 which are supposed to be equivilent to 8 cores i.e 2 cores per module, but it's not quite the truth.

Simply put you get 1.5 "Cores per module".

sloppyjoe123 · Oct 17, 2011

Yep, FX8150 runs 8 cores, each with 1 thread. i7 2600k, runs 4 cores with 8 threads.

Imagine how awesome if FX8150 had 8 cores, 16 threads

Artikbot · Oct 17, 2011

Quote:

Originally Posted by thrasherht

The key part that makes up a core is the actual processing unit inside the core, so since each module has two FPUs in it, that is 2 cores. So yes, 8 cores.

Actually, no.

It has ONE FPU per module. It has two ALUs and two FMACs per module though.

The fact of not having two FPUs per module is why the per-core IPC is so low when running all the eight threads; and it's also the reason why IPC increases so dramatically when one core per module is disabled.

ChronoBodi · Oct 17, 2011

http://techreport.com/articles.x/19514

that article finally explains what's going on...

Intel and older AMD processors do CMP, or traditional "moar cores" whereas Bulldozer fused two cores together and makes them share with each other into a module.

yuksel911 · Oct 17, 2011

don't listen to them. he can beat i5 at all ... but still i7series are the best cpu's in the world ...

_s3v3n_ · Oct 17, 2011

Quote:

Originally Posted by ChronoBodi

there's all the media talk of "OMG 8 core loses to intel 4 core!"

I think that's not really correct, should it be 4 modules vs 4 cores? But then again they look at the Bulldozer and are like "WOAH 8 cores!"

So I guess Newegg is lying.

http://www.newegg.com/Product/Produc...960&Tpk=FX8150

"Worldâ€™s First 8-core Desktop CPU"

jackbrennan2008 · Oct 17, 2011

Quote:

Originally Posted by _s3v3n_

So I guess Newegg is lying.

http://www.newegg.com/Product/Produc...960&Tpk=FX8150

"World's First 8-core Desktop CPU"

By classification it's an 8 core processors, but it's not as clear cut as that.

It has 4 modules and each module can be considered 2 cores. But instead of having 2 cores which have their own resources you have 1 module with 2 "cores" that have to share resources within the module. Which leads to a decrease in performance.

PCPer did a test where they ran a benchmark using 2 "cores". 1st test was ran with two "cores" on the same module and the 2nd test was ran with two "cores" from seperate modules (2 modules, one "cores" each).

The 2nd test was faster because each core had it's own resources and didn't have to share resources.

ChronoBodi · Oct 17, 2011

Quote:

Originally Posted by jackbrennan2008

By classification it's an 8 core processors, but it's not as clear cut as that.

It has 4 modules and each module can be considered 2 cores. But instead of having 2 cores which have their own resources you have 1 module with 2 "cores" that have to share resources within the module. Which leads to a decrease in performance.

PCPer did a test where they ran a benchmark using 2 "cores". 1st test was ran with two "cores" on the same module and the 2nd test was ran with two "cores" from seperate modules (2 modules, one "cores" each).

The 2nd test was faster because each core had it's own resources and didn't have to share resources.

so it's basically physical hyperthreading?

RonindeBeatrice · Oct 17, 2011

Quote:

Originally Posted by ChronoBodi

so it's basically physical hyperthreading?

No, hyperthreading is physical hyperthreading. This is sharing an FPU between two cores.

Hyperthreading

Quote:

Hyper-threading works by duplicating certain sections of the processor-those that store the architectural state-but not duplicating the main execution resources. This allows a hyper-threading processor to appear

AMD took the idea to a new step, but didn't quite hit the note they were going for.

Pavix · Oct 17, 2011

I see this discussion alot, to me a core is something identified via the OS, if Windows sees 8 cores then it has 8 cores irregardless of the shortcomings of shared resources. If I had a nickle for everytime I read someone say "don't compare BD to a 2600 because BD doesnt have 8 cores" I could buy AMD. If AMD does not want to compete with 8 core CPU's, even one's with 4 physical cores and 4 virtual ones, then it shouldnt put "8 core" on their boxes.

is "8 core" BD really a quad core?

ChronoBodi

WizrdSleevz

The_Hairy_Yak

thrasherht

ChronoBodi

Transhour

ChronoBodi

Malcolm

Dman

Transhour

jackbrennan2008

sloppyjoe123

Artikbot

ChronoBodi

yuksel911

_s3v3n_

jackbrennan2008

ChronoBodi

RonindeBeatrice

Pavix

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