Discussion AMD Ryzen MegaThread! FAQ and Resources

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8350rocks

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Ryzen is 1% ahead of BDW-E in single thread, according to a conversation with Robert Hallock. They are 6.8% behind kaby lake, by their own admission.

Unless you think a 200-300 MHz advantage over Ryzen is going to magically produce 20% somehow when BDW-E is starting 1% behind at same clocks. I doubt a 4.1 GHz Ryzen loses by much at all to a 4.4 GHz 6900K in anything that is optimized.

The *true* performance increase will come from the April windows patch when the scheduler recognizes SMT cores. Microcode will clean up quite a bit of things, perhaps they pick up 5-10% in some areas...but the windows scheduler is what is really killing them at the moment.
 

jaymc

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Thanks for your input Gamerk wise words I'm sure..

Here's some info I found on gaming benchmarks on Linux for the Ryzen 1800x, there few an far between and no graphics I'm afraid.

I had heard that the CPU scheduling problem is already fixed on Linux (could be wrong or maybe it's not on this distro).

Anyhow zen didn't seem to fair much better acording to this website:
http://www.phoronix.com/scan.php?page=article&item=amd-ryzen-gaming&num=1
 
To the various people replying against the vid I posted you are missing the point. This isn't a comparison to prove the fx 8350 was a better purchase. There are 3 key points that are very valid:
- it's looking at a lower core count part vs a higher one. If you want to compare to Ivy, compare to the ivy i5, the trend is the same
- it's looking specifically at the 'fact' that game reviews use to test 'cpu gaming performance' by using unrealistically lowered resolutions to 'predict' future performance.
- what it shows is very clear. The higher core count part doesn't get slower at gaming as time goes on with much more powerful gpus vs the lower core count part. In fact the delta between the two diminishes over time in favor of the higher thread count. This is despite the inherent weaknesses in fx.

How this relates to ryzen: long term it suggests ryzen should maintain pace with or possibly catch current gaming parts like the i7 7700k. Despite all the comments to the contrary higher core count parts are the better option for longevity (the same is true for Intel higher core count parts, so no this doesn't mean ryzen will catch the 6900k just like fx doesn't outpace the Ivy i7). The critical point though is in 3 years time with a gpu 3x the speed of Pascal Titan, ryzen will be in the same relative position (or arguably a tad better) vs Intel and not massively behind which is what the reviewers are trying to infer with the low resolution benchmarks. They are jumping to a conclusion that simply isn't backed up by any data.
 

jdwii

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I rarely do this but i will say that once again something seems off and maybe we all need to wait

http://www.guru3d.com/articles-pages/amd-ryzen-7-1800x-processor-review,12.html

Ryzen should be doing better, pretty sure we got an issue Gamer and so forth think it could be SMT which sounds very feasible to me the benchmarks above would never allow Ryzen to test that high if IPC was real low.

I heard Linux/Unix should be getting a patch soon to.

I'll personally buy Ryzen once i get more $$$ and if this gets fixed. Something has to be wrong no other way around it, 6900K beats a 7700K In a decent amount of titles even when the 7700K is at 5Ghz Ryzen should be at least close to that as Ryan Shrout from PC perspective notes in his review
 


And "elegance" is also not my point; if it were better than Intel with no doubts, no one would say its a "bad" thing, but a "smart" thing, maybe?

AMD just chose that strategy (clusters) not for "performance" reasons, but business reasons. Like I said, AMD has to live in 3 market segments with a single uArch: server, consumer and multipart (think consoles). They had to define a "unit" that can be moved across designs easily and attack the important markets they can cash-in from. This is just a similar approach to the modules in BD, but a bit more clever and forward thinking (my take at least).

So, this is just a counterpoint to say it's not because the team "made a mistake" when choosing the CCX arrangement, but it was a conscious decision (from what I can see). I did like the "modules" approach in BD, but it didn't pan out how they wanted; now the CCX seems to be following the same principles that backed up the "module" approach in BD, but now done in a better way.

Cheers!
 

truegenius

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juanrga said:
Or maybe the design with a partitioned LLC linked via a slow interconnect is just ridiculous to start and no magic scheduler will hide the deficiencies of that. I have been thinking on some other similar design and don't remember anything. Everyone, Intel, ARM, IBM, Sun,... uses unified LLC.

For practical purposes Ryzen is working as two quad-core CPUs glued together in a die.
why they used ccx instead of going octa ?
they are probabily using same die for 4 core part ( why ? ) too means yields have to be ridiculous ( or purposedly disable cores ) means even more performance loss and different perfromance for different core combination ( 4+0, 1+3, 2+2 )

btw is there any review in which they have tested by disabling cores to replicate 4/6c parts and predict their performance and to rule out ccx causing perfomance issue by comparing 4+0, 3+1, 2+2 config ?
 

juanrga

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The die size is larger than that. Chip-architect estimation is incorrect. He got that number from measuring a die shot has been photoshoped by AMD.

The correct size is behind a paywall at SA, but I can say that the die is bigger than my old estimation of ~205mm^2...

Edit: The exact value is behind a paywall, but next link gives a very good hint to which is the real die size

https://twitter.com/TMFChipFool/status/839279240948367365?p=p
 

juanrga

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AMD made several outstanding claims about performance (CB, Blender, gaming,...) that have been disproved by reviews. For instance both PCWorld and PCPer admit that cannot reproduce the CB scores. PCWorld: "My own tests don’t quite match AMD’s results." And PCPer writes: "Still, the 8% gap between the 6900K and the Ryzen 7 1800X at 3.5 GHz tells me that AMD’s claims of equal IPC appear to have been overstated." GamerNexus even goes beyond and offer us an analysis of how AMD inflated gaming numbers:

At this point, you might be left feeling disillusioned when considering AMD’s tech demos. Keep in mind that most of the charts leaked and created by AMD revolved around Cinebench, which is not a gaming workload. When there were gaming workloads, AMD inflated their numbers by doing a few things:

In the Sniper Elite demo, AMD frequently looked at the skybox when reloading, and often kept more of the skybox in the frustum than on the side-by-side Intel processor. A skybox has no geometry, which is what loads a CPU with draw calls, and so it’ll inflate the framerate by nature of testing with chaotically conducted methodology. As for the Battlefield 1 benchmarks, AMD also conducted using chaotic methods wherein the AMD CPU would zoom / look at different intervals than the Intel CPU, making it effectively impossible to compare the two head-to-head.

And, most importantly, all of these demos were run at 4K resolution. That creates a GPU bottleneck, meaning we are no longer observing true CPU performance. The analog would be to benchmark all GPUs at 720p, then declare they are equal (by way of tester-created CPU bottlenecks). There’s an argument to be made that low-end performance doesn’t matter if you’re stuck on the GPU, but that’s a bad argument: You don’t buy a worse-performing product for more money, especially when GPU upgrades will eventually out those limitations as bottlenecks external to the CPU vanish.

Ryzen is a good 10% clock-for-clock behind BDW-E in applications. "moyenne applicative" means average of applications
getgraphimg.php


And a good 20% behind BDW-E in games. "moyenne jeux 3D" means average of games
getgraphimg.php


A BDW-E overclocked to 4.2--4.3GHz will increase the gap compared to a Ryzen overclocked to 3.9--4.0GHz.

New schedulers will not solve magically the muarch deficits. Just as they didn't solve for Bulldozer. I remember the multiple claims that Bulldozer scheduler was going to improve performance significantly. Then AMD and Microsoft did released two patches and average performance gains were 2--5%.

Note that above graphs already include most of the effect of a smart scheduler in the performance bars label "Core Parking OFF". I am using this better case for obtaining the above 10% and 20% gaps.
 

juanrga

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I am preparing an article about my predictions about RyZen where I explain why I predicted what I did, where I was right and where I failed and why. It is still a draft, because I am waiting for Anandtech review 2. Regarding CCX I write:

I also predicted Zen would come in four-core clusters. This is what AMD names the CCX. My proposal was based in a hypothesis about AMD wanting to increase the minimal core count to four and a hypothesis about reusing the cluster for the APUs and for the semicustom division to reduce the design costs with a modular approach. My prediction was that Zen would come in groups of CCX with SMT disabled or not. For instance 4c/4t for the lowest Ryzen CPU and then 4c/8t and 8c/8t for the intermediate models, and 8c/16t for the flagship AM4 socket model. With servers coming in combinations of 8c/16t and 16c/32t for the dual die socket (SP4), and 16c/32t and 32c/64t for the quad die socket (SP3).

MOD EDIT: <LINK DELETED>

Reusing a basic compute unit of four-core helps AMD to reduce the R&D cost of design/testing/validating different configuration from mobile to server. You only have to design/validate/test the CCX once, and then reuse the CCX on different dies. For instance if tomorrow someone approach AMD for a semicustom desing. The customer only would chose the number of CCX it want. And AMd would only place the CCXs on a die and validate the interconnections between CCX and the rest of the SoC sving both money and time compared to a non-modular design from scratch.

My vision was quad-core modules but with a separate LLC module. The die, in my vision would be

[ compute-module ] <--> [ cache module (L3) ]<--> [ compute module ]

^^^^ I will prepare a proper diagram when have time. Meanwhile I expect the above is enough to clarify my vision.

With this design the L3 cache would be a true LLC for all cores. Surprisingly AMD chose a weird CCX approach with local L3 and connected to the other CCX (and its local L3) through a slow interconnect: only 22MB/s !!!!!!

I see in other forums people pretending that this weird configuration with split LLC is a consequence of RyZen being designed for servers, not games. That is an excuse. Power8 (IBM) or Vulcan (Broadcom) are designs exclusive for servers and both have unified LLC. Haswell/Broadwell/Skylake... are designs optimized for server and have unified LLC.

CPCHardware did some testing with engineering samples and found that 4+0, 3+1, and 2+2 have different performance. It seems commercial chips are constrained to having symmetric CCX or full disabled CCX. This means the next configurations:

6-core = 3+3
4-core = 4+0 or 2+2
 

daerohn

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the page below supposed it will be released 2nd half this year. Also there is a picture showing intel road map for 2017.

http://www.pcworld.com/article/3168827/components-processors/intels-8th-gen-coffee-lake-chips-reuse-14nm-process-as-other-core-cpus-ease-into-new-tech.html

infact I do not care for what Intel plans for this year. I haven't been purchasing Intel since 2004. and do not think to switch in near future.
 

8350rocks

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CB scores have been duplicated by various reviewers routinely.

The only one that has been errant is the 6900K, which in some cases has more variance.

Stock 1800X routinely produces 160-163 single thread in cinebench single core depending upon cooling solution allowing turbo for the full duration or not. Stock 6900K has produced between 155-161 typically in those same benchmarks.

Not earth shattering, but the 1% is there.

EDIT: It would also be prudent to point out to those viewing your graphs that they are comparing a 6950X in those benchmarks, and the gap you are referring to is from 2 more cores...or more prudently a 20% advantage in resources.
 

salgado18

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juanrga

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Precisely several reviewers have noted that cannot reproduce the CB numbers given by AMD and thatr the IPC is less than AMD promised

PCWorld: "My own tests don’t quite match AMD’s results."

PCPER: "Still, the 8% gap between the 6900K and the Ryzen 7 1800X at 3.5 GHz tells me that AMD’s claims of equal IPC appear to have been overstated."

Also the above graphs are NOT for a 6950X.

Nous cadençons pour ce test nos FX-8350 (Piledriver), Ryzen 7 1800X (Zen) et Core i7 6900K (Broadwell-E) à 3 GHz.

It is 8-core Broadwell vs 8-core Ryzen, vs 8-core Piledriver. Ryzen is 10--20% slower than Broadwell because the IPC is well below Haswell and close to Sandy Bridge level.
 

jaymc

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Great video ... and also reassuring.. think the April update will do plenty for Ryzen.

I was thinking to myself, with all the moaning going on... I don't know about you guys but I'm still sold on it anyway...

I think most people are !

But still having a little moan about few frames per second here an there... I'm looking forward to seeing how AMD's sales of Ryzen are going, because I can't help thinking that even though the gaming community is complaining...
They are probly all doing it while ordering Ryzen anyway... regardless of the teething problems that is :)
 

8350rocks

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You are quoting games not optimized for IPC measurements? I think the argument is flawed.

All the actual IPC benchmarks point to parity with broadwell. Using gaming benchmarks with flawed windows schedulers, microcode bugs and everything else currently at play is a flawed attempt to justify a bad prediction.

Once the scheduler issues and other things are fixed, we can discuss games. As it stands right now, Ryzen shows parity with broadwell *in spite of those flaws* in IPC driven benchmarks like cinebench. What do you think the benchmarks will look like when those things are corrected??

Ryzen is well past Sandy Bridge in IPC. There is not a valid argument to present that shows otherwise.

 

8350rocks

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I am building a 4K prosumer gaming rig for productivity and gaming.

Already have everything but the GPU picked out: https://pcpartpicker.com/list/cVX3BP
 
But I've finally gotten everything ordered for my Ryzen build, and PCP FINALLY has all the parts I ordered actually on their site:

PCPartPicker part list / Price breakdown by merchant

CPU: AMD RYZEN 7 1700 3.0GHz 8-Core Processor (Purchased For $329.00)
CPU Cooler: MSI CORE FROZR L 71.3 CFM CPU Cooler (Purchased For $49.99)
Thermal Compound: Thermal Grizzly Kryonaut 1g 1g Thermal Paste (Purchased For $8.95)
Motherboard: MSI X370 GAMING PRO CARBON ATX AM4 Motherboard (Purchased For $179.99)
Memory: G.Skill TridentZ RGB 16GB (2 x 8GB) DDR4-3200 Memory (Purchased For $171.59)
Storage: Crucial MX300 275GB M.2-2280 Solid State Drive (Purchased For $89.99)
Storage: Western Digital BLACK SERIES 1TB 3.5" 7200RPM Internal Hard Drive (Purchased For $74.99)
Video Card: EVGA GeForce GTX 1080 8GB FTW Gaming ACX 3.0 Video Card (Purchased For $594.89)
Case: NZXT S340 (Black/Red) ATX Mid Tower Case (Purchased For $59.99)
Power Supply: SeaSonic G 550W 80+ Gold Certified Semi-Modular ATX Power Supply (Purchased For $69.99)
Case Fan: Thermaltake Riing 12 RGB Triple Pack 40.6 CFM 120mm Fans (Purchased For $56.99)
Total: $1686.36
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2017-03-08 18:52 EST-0500
 

jaymc

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@8350rocks Interested to know what you are getting out of your Liquid Cooler... quite reasonable at $125 nice.

@james mason Also nice build mate... notice you went with the 1700...Overclocked to 1800x speed I presume.

Can't wait to build one I'm going to donate my current 8350 to my children with an rx480 in it. An I'm confident they will still get plenty of enjoyment out of the old dog.!!

MOD EDIT: Off-topic references removed from this and prior posts
 
I'm looking forward to seeing how Ryzen performs with the 1080 ti, and especially Vega. On the one hand, as GPU's get faster it should create a performance gap at high resolutions. But on the other, most recent comparisons have showed lower CPU usage with AMD cards against comparable Nvidia cards. But there hasn't really been anything to compare the 1080 and Titan to on the AMD side. If that trend holds true, it could provide a significant boost to Ryzen in high end gaming, assuming Vega meets expectations.
 

Nope 1151

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Juan, would AMD have been better off by splitting the L3 cache and using the actual ram sticks (L4?) as the "unified cache"? Could you explain the pro/cons (Aside from the obvious, "Less cache").

The way I see this is that AMD chose to aim for the server market, with good reason. The last thing Intel wants is for a company to say that they can easily replace Intel systems with AMD ones.

Competition is good.
Also, Mini-itx yay!
See this:
https://smallformfactor.net/news/biostar_racing_x370-gtn_itx

 

dgothi

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i5 get 6 cores is a possible.it will be cost more because it is similar to Intel's 5820k 6 cores however, 5820k have hyperthreading. I assume i5 might get 6 cores OR 4 cores with hyperthreading either. we will wait and see :)
 

dgothi

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people who bought Ryzen 1700 so it received very well review on amazon, I am surprise. I have not decide which do I want to buy intel or Ryzen. No rush. Intel i7-7700 might be safe to buy? Maybe since it is maturity, right? I might buy either Ryzen or Intel next two weeks.
-DG
 


If you game a lot, the i7-7700 might be better, but if you do anything else, Ryzen is the way to go.
 

juanrga

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Game benches, if well made can measure IPC. "Well made" means one is not introducing GPU bottlenecks of any class that artificially reduce the CPU performance. Example of bad measurement:

2017-03-06-image-16.jpg


The settings used have generate a GPU-bottleneck and all the CPUs perform the same because all them are waiting for the GPU to do its graphic work.

Good measurement showing CPUs real performance differences:

2017-03-06-image-18.jpg


But let us ignore games and check only applications. FX-8350 (8-core Piledriver) vs Ryzen 7 1800X (8-core Zen) vs i7 6900K (8-core Broadwell-E) all them at 3 GHz

getgraphimg.php


Even with a smart scheduler that reduces SMT penalty on Zen, we can check that Broadwell is faster than Zen. In some specific workload as x264 Zen is slightly ahead , but in others like WinRAR Zen is clearly behind. Overall ("moyenne applicative") Broadwell is a good 10% ahead of Zen on average.

A 10% behind Broadwell put Zen at the Sandy Bridge level more or less. This was expected because the Zen microarchitecture is inferior to Haswell. Reviews finally confirmed this.

Cinebench shows the same pattern than the above average over applications. The marketing slides given by AMD don't reflect reality, as reviewers have confirmed:

PCWorld: "My own tests don’t quite match AMD’s results."

PCPER: "Still, the 8% gap between the 6900K and the Ryzen 7 1800X at 3.5 GHz tells me that AMD’s claims of equal IPC appear to have been overstated."

This is PCPER measurement of IPC using CineBench

clock-cb15-1.png


Ryzen performs like Ivy Bridge more or less. On Handbrake the IPC od Ryzen is better and matches Broadwell

clock-handbrake.png


but on Audacity the IPC of Ryzen is much worse than Broadwell

clock-audacity.png


On workstation-class applications the IPC of Zen is about 10% lower than Broadwell. On games the IPC of Zen is about 20% lower than Broadwell. Overall, a 15% below Broadwell is Sandy Bridge territory.