AMD CPU speculation... and expert conjecture

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8350rocks

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Why on earth would you want to calculate 12 hours per day?

99.99999999999999999999999999999999999% of users don't experience FULL LOAD for 4 hours per day, much less 12 hours.

If you're talking about general use for 12 hours per day, then calculating full load difference for 6 hours per day is sufficient to give you a decent idea there...
 

8350rocks

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XBone likely DOA before arriving, launch delayed in more than half the world:
http://semiaccurate.com/2013/08/16/xbox-one-backpedaling-chronicles/

NVidia slumping, trying to dodge questions about lackluster corporate performance:
http://semiaccurate.com/2013/08/16/nvidia-tries-painting-rosy-outlook-tegra/

 

Cazalan

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Above 3Ghz isn't too comforting. Above 4Ghz would be. So we likely have to go back to the older charts where SR is 10-15% faster than Piledriver. Clock speed reduction but higher "IPC". On the plus side they should be cheaper to make and use less power. Good for the mainstream user but FX-6350/8350 will remain top end for desktop.
 
AMD needs to be very careful here because one of the few desktop spaces their really good at / dominate in is large multi-threaded applications where someone would need to buy a significantly more expensive Intel CPU. Abandoning that segment by not producing a six ~ eight core CPU would be a very bad move. They also need to come up with a dual socket friendly implementation, extremely niche but there is a market for massive core count on the desktop. Their bread and butter is definitely in the budget four core APU market priced at $150 or less seconded by the gaming segment that is about to appear.

Thing is, APU's instantly lose their value the moment you transition to medium sized (not Mini-ITX) desktop systems as there are cheap dGPU's that are better for the task. The iGPU on their chips takes up a very large portion of the die, in a desktop system that portion is just wasted space and their value advantage goes down the sh!tter. This is why they absolutely need at least a six core solution (three module), or hasn't anyone noticed how much value is in the fx-6xxx series. Also AMD is now trying to enter the gaming segment and being the native uArch that the two most popular next gen consoles have is a gigantic advantage. Gaming on any serious level requires a dGPU, APU's are fine for mobile or SFF box's but they fail miserably once you ratchet up the specs (their just not designed for that market segment). So AMD is going to need a CPU to pair up with a 760/770/780 or even some future 8xxx class dGPU, an iGPU would be a waste of die space and thus lost potential performance.

So while we can debate the need for a successor to the fx8350 (I personally need one), it's very clear that they will need a successor to the fx-6350 and that successor won't have much use for an iGPU.

Again though, look at what HSA allows AMD to do: They can offer a CPU+APU combo (HSA) and do something that looks like:

CPU for generic tasks
APU for OpenCL/CUDA/HSA
Discrete GPU for rendering

This would allow, for instance, fully hardware accelerated effects without a hit to FPS, as neither the CPU or GPU would have to do any additional processing. That's the big advantage HSA allows to happen. Using this schema, you wouldn't need a powerful CPU for gaming, as you could potentially offload a LOT more processing without a noticeable performance hit, making FX a dead-end arch. Coincidentally, this is the way I think things are going to head for the desktop going forward.
 

noob2222

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you mean this rumor? http://news.softpedia.com/news/AMD-and-GlobalFoundries-Interested-in-FD-SOI-for-the-20-nm-Process-267519.shtml
or http://www.xbitlabs.com/news/other/display/20120428083057_AMD_Globalfoundries_Others_Set_to_Use_Fully_Depleted_SOI_with_14nm_20nm_Chips.html

or some other rumor made up on another forum claiming "bulk"?

I don't know what you mean by "only one tech site even posted the "rumor" by a person that's not even employed with AMD for nearly an entire year."

http://www.brightsideofnews.com/news/2012/3/6/amd-ditches-soi-kaveri-goes-bulk-at-gf2c-more-details-from-the-new-wsa.aspx

AMDs CFO Thomas Seifert --- http://www.engadget.com/2012/09/17/amd-cfo-thomas-seifert-resigns/

hes gone and didn't disclose why he left, maybe the engineers told him that bulk only won't work for entheusiasts and is only good for laptops/ps4/xb1. who knows, that AMD ditching SOI claim was over a year ago, but hey nothing ever changes.

I didn't say that kaveri will catch the FX-6350. I said that the CPU would be behind the FX-6300.

The Softpedia article (Apr 2012) claims that about frequencies. However, the PC-watch article (July 2013) claims that Glofo spent near an entire year mastering high-performance bulk for kaveri. Moreover, Glofo claims now that his high-performance bulk 28nm process can scale above the 3 GHz.

GF1.jpg


so .. Kaveri is going to improve trinty by going from 4.2 ghz base clock to intel's standard 3.5? If thats the case, then I don't see kaveri getting close to the 6300 @ stock. Kaveri needs ~4.5 ghz for that. If kaveri is bulk, my hopes of seeing a decent cpu out of it are even lower.

- AMD is replacing 8-core Opterons by 4-core Berlin.
- Warsaw will use Piledriver => there is no 6/8-core Steamroller modules.
- Kaveri comes as 2/4-core.

Does it make sense for you that AMD will release 6/8-core FX steamroller or similar chip exclusively for the desktop? Not for me.

SR FX are not exclusive to DT. those are the 2p-4p server chips. If warsaw is a PD refresh, then we should see some in the AM3+ DT socket as well. When/if SR moves to 2p-4P we will see SR-FX or whatever they decide to call it in 2015.

The existence of Warsaw doesn't mean the elimination of all other 2p-4p cpus. If kaveri/sr FX are both 28nm (SOI or not), AMD wants to make the best profit possible, and with GF being limited on production, that leaves Kaveri being the most viable option until stocks are full, then we may see SR 28nm (SOI) 2P-4P cpus.

Right now AMD doesn't know when that will happen or if that time will come AFTER Excavator is ready to produce. If you want an example of what happens when you don't know the future, look up the fate of AMD's deccan cpu (bobcat 28nm).

apu.roadmap.jpg

man, 28nm production in 2012, thats going to be great

If you don't know if you will have enough fab capacity to produce a product, do you A: advertise the crap out of it and hope it happens or B: remain silent? In all likely scenario's, SR-FX fate is determined by how well kaveri is selling.

Truth is, only the inside at AMD know wether they are using SOI or not. The only rumored proof otherwise is some article posted 1.5 years ago on BSN by a CFO thats no longer with AMD.
 

griptwister

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Geeze... this is SteamRoller people, not Half Life 3. We haven't heard anything about AMD "delaying" anything. These are just rumors. Lol, think about it...

Rumor: Kaveri being delayed...

Truth: Kaveri not being delayed.

Rumor: FX series CPUs being canceled.

Truth: No one ever said anything about AM3+ line up being discontinued.

Let's not assume things...

My favorite quote: "Assuming makes an "@$$" out of "u" and "Me."

I honestly believe SteamRoller is going to either be AM3+ or AM4 supported. I think AMD is bringing BIG performance. Luckily, I'm not in a rush to purchase a CPU. It'd be nice if AMD released them now... But I'm not rushing it.
 

hcl123

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They have 16 cores already... and they have "opened" their server platform to concentrate more specifically on Seamicro. Doing 20 cores would be easy with a process node shrink, like 5 module CPUs. But then the big question is if its worthed !?.. a 5 module CPU perhaps will need 3 channels DDR3 DRAM (but DDR4 could even be overkill with 2 channels), it would make yields worst, it will clock lower, and it would be quite more expensive, and this for just a little more performance compared with a 2s server systems with 32 cores... 40 cores will add little to this.

I think AMD will skip this phase. Next for servers, perhaps 28nm FD-SOI, which is ~half a node compared with 28nm bulk or PD-SOI and so ~ a full node shrink compared with actual 32nm PD-SOI, will be 4 thread/cores modules (Excavator ?), and so a 2s (2 sockets) server will have 64 thread/cores... and DDR4, which is double the bandwidth, for the same 4 channels in a MCM SKU.

This is a 32 cores chip (16 per die in MCM).. and its double cores of now.

I don't think they would "open" a platform so that anyone can do their own server mobo reference designs, and them leave them without any CPU to put on those mobos.

 

hcl123

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"" Don't say that ""... all those "users" want is a desktop part that is low power at the rated commercial speeds, but then OC the heck out of it... and still think they are low power LOL

Hardly they think, that IB as example OC to 4.8Ghz (Hasfail can't get this high on air) already consumes more power than "Centurion" at the same speed... big LOL

http://pctuning.tyden.cz/ilustrace3/obermaier/4770K/scaling_sandy.png

[ CLEARLY SandyBridge is a better OC... and no that is not a IB fail, simply if you tweak for low power you lose clock ability... just as that simple... that is why HSW reliable at 4.8Ghz only on water... you can't have your cake and eat it at the same time, ask low power then you're really asking for low clock)
 

hcl123

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But first you need games to take advantage of that.

Like i ranted here before lol (edt)... ppl shouldn't be ranting against the hardware vendors (including AMD intel or ARM), ppl should be ranting against the software houses, if they want real high performance and more juicy features.

 

Cazalan

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It's also the difference of FreeBSD derived PS4 OS vs Windows 8 (CE or embedded or whatever they call it).

For AMD's sake it's best if both sell very well.
 

hcl123

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I think is kind of more than set in stone... there wouldn't be any 20nm FD-SOI. From IBM side will be high performance 22nm FD-SOI, and from the STMicro/Glofo side will be "generic" 28nm FD-SOI that is more like *25/24nm*, but AMD might get this with booster tech(more than enough causes for delays)... then the jump is for 14nm FD-SOI (with 20nm BEOL- like the 14nm and 16nm Finfet on bulk of Glofo and TSMC).

All those are old "rumors", the 20nm FD-SOI should be dead.

Also Thomas Seifert was fired (and for some good reasons it might had), i wouldn't count as reliable now, any news coming from his "short" time.

 
you mean the other way around right? because its weaker, xbone will be the baseline. Anyways, I went through some of that thread and people there don't understand anything about huma. Most people on neogaf seem to be technologically inapt, all covered with the bullshit of fanboyism.

I doubt anyone who see huma would think that it makes the ps4 better right now even if the xbone does not have it. From the original article they quote, there is no talk about xbone, huma or anything relating huma's advantage to ps4 from AMD. Almost all current engines still run cpu physics and very little GPGPU so I don't know who would be able to calculate the advantage of huma in gaming.

Even if xbone did not have huma, it would be because it doesn't need it. The move engines will be able to put data where it wants and when. There also no reason to think the DDR3 pool is not coherent between gpu and CPU, which would be all thats needed for huma.

The advantage of huma won't come until programs are written on HSA enabled compilers. This won't come until the real hardware is out. People who publish articles like that probably don't know what they are writing about.

 

hcl123

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@esrever

Yes i think you are right in a sense. Xbox one doesn't hUMA from the DDR3 DRAM side, which will be like old method controlled by the CPU side, but Xbox one will have the IOMMU kind of tricks for virttual addressing and will have ESRAM that will function like a hUMA pool (kind of) but controlled by the GPU side. Yet that CPU can see and write to this pool in a coherent way... matter of fact the ESRAM controller does more than any ordinary hUMA

http://www.vgleaks.com/durango-gpu-2/2/

ESRAM

Durango has no video memory (VRAM) in the traditional sense, but the GPU does contain 32 MB of fast embedded SRAM (ESRAM). ESRAM on Durango is free from many of the restrictions that affect EDRAM on Xbox 360. Durango supports the following scenarios:

... Texturing from ESRAM
... Rendering to surfaces in main RAM
... Read back from render targets without performing a resolve (in certain cases)


The difference in throughput between ESRAM and main RAM is moderate: 102.4 GB/sec versus 68 GB/sec. The advantages of ESRAM are lower latency and lack of contention from other memory clients—for instance the CPU, I/O, and display output. Low latency is particularly important for sustaining peak performance of the color blocks (CBs) and depth blocks (DBs).

The problem is ESRAM is too small for a large quantity of large textures, that is why texturing on Xbone will compressed and decompressed on the fly by the GPU. This will impact performance in a way, but provides identical functionality of hUMA. I think Xbone games will tend to have a little less high quality texturing and so a little less image quality, but apart from that it will be indistinguishable for the human eye, most included FPS(which will be kind of lower to).

I think ppl re pissing at the wind, doubt it will be possible to benchmark any of this systems, every piece of software must have an encryption key (for both, and worst PS4 is FreeBSD), so you don't just grab a windows benchmark from the net and use it.

Best of both worlds will be to have hUMA and ESRAM (Texturing from ESRAM, Rendering to surfaces in main RAM, Read back from render targets without performing a resolve (in certain cases) ).. if Kaveri have both it would be worth the wait, and nobody will be ranting about GDDR5 lol.
 
Oh, I didn't see this blog post... I just got it from the AMD Dev mailing list:

http://blog.documentfoundation.org/2013/07/03/amd-joins-the-document-foundation-advisory-board-to-accelerate-libreoffice/

Looks like they joined LibreOffice to work with them developing stuff to use the GPU (or APU thinking HSA). I'd love to see OpenSheet using the GPU for lookups, haha.

Cheers!
 
ESRAM management is not fun; ask PS3 developers how hard it was to keep the CPU going to know what I'm talking about.

HUMA allows to avoid copying memory between CPU and GPU contexts. This copying increases latency by a significant degree, which in turn affects performance. To get around this limitation, you typically see, for instance, smaller textures used that are repeated over and over again, allowing for a smaller data transfer. By giving the GPU access to main memory, you avoid needing to copy textures to the GPU's memory context, allowing, theoretically, much larger and more detailed textures to be used without a performance penalty.
 

8350rocks

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Middleware plays a huge part in that though...what APIs are used, and how effectively they're used come largely into play in gaming performance across a broad spectrum of OS benchmarks.

If DX11 runs well on BSD/Linux then Windows loses 90% of it's advantage.

EDIT: Obviously it's not currently feasible to use on either one...being my point entirely.

 
I do believe I made comments awhile back on how important the CPU and GPU operating in the same memory space was. Funny to see people's reaction like it's something new.

@Gamer
APU's are useless in desktop applications where a dGPU exists. The iGPU consumes ~50% of the die space that could go to more processing power or a cheaper unit. That doesn't preclude HSA and other combined approaches, it would be trivial to include a slimmed down iGPU core that acts as an HSA co-processor and then use the extra space for a third module (possibly even fourth depending). Also the "FX" design ~IS~ the new design, their all the same modular uArch aka Trinity / Richland. AMD designed it to be modular and like lego's. Try to think of a "desktop" part as an "APU" have six ~ eight cores but a really small / weak iGPU. It would operate under the assumption that you most likely already had a dGPU present.
 

juanrga

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Confused schedulers, non-optimal compilers, bloated APIs...



1. A specific case was discussed here before

2. AMD performs better under linux, because software is more modern and well-threaded than Windows, which is usually developed with Intel in mind: Wintel.



My point was that the optimized software run 2x faster in the same hardware, which means that the 'standard' software ignores a lot of the hardware potential.



One can make comparison by performance by price... Regarding MT performance one can say roughly that:

FX-4 ~ i3
FX-6 ~ i5
FX-8 ~ i7

Besides that I already announced that I am preparing an article about Kaveri performance and regarding the Steamroller CPU I am comparing it to a pair of i5. Happy?



HSA != OpenCL
 

juanrga

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I have always tried to differentiate facts from fiction and reality from hopes. I have clearly stated in more than one occasion that 4C Kaveri cannot replace a FX-8350, regarding CPU performance and ordinary software (at best, kaveri could, as APU, beat the FX using HSA software).

I already speculated about the possibility of pairing a APU with a dGPU and using the iGPU for compute.

Moreover, sometimes we try to believe that 'real' gaming is made in top CPUs/GPUs but nothing more far from reality: less than a 1% of gamers have a 7790 or a Titan. Those are marketing cards. The same about CPUs. The average gamer has a dual-core; less than a 1% has an octo-core CPU.

I understand that some people want/hope a Steamroller-based 6/8/12/16 core CPU. The point is if those chips are coming and my answer, with all information I have at hand, is "NO".

People thinking otherwise would reply the points in my previous post. For instance, why will AMD release a Steamroller 8 core CPU for the 2014 desktop, without using those modules in Warsaw CPU.
 
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