New Zen microarchitecture details

Discussion in 'CPUs and Overclocking' started by Dresdenboy, Mar 1, 2016.

  1. KTE

    KTE Senior member

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    Yes, but here's the kicker:

    i) there is no such application targeting all... Accurate for all.
    ii) showing a CPU in a bench highly optimized/tuned to extract good performance will generally not be reminiscent of RW apps.

    In the end, the point of benchmarks is to be able to advise people on what is worth purchasing for them for their usage patterns.

    I'll dissect Excavator PR from actual results to show this as soon as I get some time.

    Sent from HTC 10
    (Opinions are own)
     
  2. Ajay

    Ajay Platinum Member

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    Since neither axis is labelled for the Zen vs Excavator chart - what we have here is a pure marketing chart. There is no valid engineering data and, hence, no valid conclusion can be drawn from it. This is pure pixie dust :)
     
  3. Burpo

    Burpo Diamond Member

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    Lol, that slide has been altered so many times.. This is the sloppy one where the word Zen doesn't even line up with the word Excavator.. Fonts & size are different.. The original slide had no names below the graph..
     
    #2053 Burpo, Jun 21, 2016
    Last edited: Jun 21, 2016
  4. ElFenix

    ElFenix Super Moderator and Elite Member
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    measuring pixels as if the marketing flunkie that put that chart together (several times) was at all that accurate is like converting the bible to numbers to predict the date of the apocalypse
     
  5. JoeRambo

    JoeRambo Senior member

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    And if Bible was written by AMD marketing, then we'd be @ ~5th coming of Jesus by now.

    This thread keeps going without any real info and leaks. Wake me up when we have a solid estimate of clocks, then we can start making educated guesses about perf if AMD did not screw up design. Remember, any Intel gen since Sandy will destroy Zen with ease if it has clock advantage that is substantial enough.
     
  6. guskline

    guskline Diamond Member

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    Polaris is on the radar screen now and AMD needs to maximize it, but ZEN will soon need to release more concrete info.

    Fortunately for AMD, Broadwell E, though an improvement has been somewhat stymied by price.

    Hopefully we will see some more concrete info on Zen in the next 60 to 90 days.

    Hey, I have an idea! How about AMD "hiring" the guy that went livestream this morning from China showing what purported to be benchmarking a RX480!:eek::':)cool:
     
    #2056 guskline, Jun 21, 2016
    Last edited: Jun 21, 2016
  7. Dresdenboy

    Dresdenboy Golden Member

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    Of course, more leaks would be nice. But to your example: same is true for ARM, MIPS, PIC, AVR at high enough clocks. ;) So no point has been made.
     
  8. nenforcer

    nenforcer Golden Member

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    While we all wait for some more interesting news on AMD Zen processors and AM4 Promontory chipset

    It's has been announced that Zendaya

    [​IMG]

    will be the official spokesperson for the upcoming chips. You heard it hear first.
     
  9. The Stilt

    The Stilt Golden Member

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    Based on the Polaris overclocking and power draw results, the 14nm LPP process looks to be significantly worse than I expected (and my expectations were non-existent to begin with) :'(

    The reference cards are at least somewhat limited by the cooling, however the < 1350MHz (average, based on reviews) Fmax is still extremely disappointing. Power delivery wise the reference cards are absolutely fine since they feature a six phase digital VRM. Also a card featuring GPU this small, running at clocks as low as ~1266MHz should not violate the PCI-E device power delivery specifications D: I'm mentally fully prepared to see Zen failing,l however I'll still be extremely gutted if it happens because of the manufacturing process. And frankly I don't see any other way Zen to fail, since I'm pretty confident about the design itself.
     
  10. coercitiv

    coercitiv Golden Member

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    Their power consumption numbers simply do not match their perf/w claims.

    Starting from now, any new claim they make about Zen better be backed by a live demo.
     
  11. ShintaiDK

    ShintaiDK Lifer

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    Welcome to the world of reality :)
     
  12. ShintaiDK

    ShintaiDK Lifer

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    Saying they outright lied would be an understatement. Its FX all over.
     
  13. Arachnotronic

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    I never thought that Polaris would match Pascal in terms of performance/watt since NVIDIA has had a pretty solid lead there. But a 14LPP product, given how nice FinFETs are, failing to compete on performance/watt with a TSMC 28nm part is really unfortunate and disappointing.

    I wouldn't put the blame entirely on the process. As I have said on these forums before, 16FF+ is a more efficient process than 14LPP, but GTX 1080 is ~82% more efficient than the RX 480 according to TPU. The majority of that delta likely comes from architecture, not process.
     
  14. antihelten

    antihelten Golden Member

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    As you say it looks to be mainly an issue with the Polaris architecture not the 14LPP process.

    GTX 1080 is 60% more efficient than the GTX 980.
    RX 480 is 76% more efficient than the 285*.

    So it would seem that AMD has gotten at least as big an increase from their node jump as Nvidia (just doesn't help much when they were as far behind as they were in the first place).

    *This is based on TPU's numbers, they don't have any power numbers for the 380 unfortunately, so I used the 285 instead.
     
  15. KTE

    KTE Senior member

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    Reality is enthusiasts always make sweeping oversimplified comparisons and look at process to create hugely unrealistic power/performance metrics.

    14nm or even if they had 7nm, wouldn't mean anything. They need Skylake clocks and power brackets at launch, or, we'll be looking at another too little too late product.

    It needs to be on par IPC wise but 25% short on clocks and power to just match the Phenom launch. I personally cannot see it happening.

    Sent from HTC 10
    (Opinions are own)
     
  16. The Stilt

    The Stilt Golden Member

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    I don't think I've ever been anywhere else :sneaky:
     
  17. The Stilt

    The Stilt Golden Member

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    There appears to be huge variations in the leakage between the different Polaris 10 ASIC specimens. The factory programmed ASIC leakage value (SIDD) can be read from the fuse registers (interpreted as ASIC "Quality" by GPU-Z) and here is what some of the review samples had:

    High = Higher SIDD (lower voltage operation, runs hotter)
    Lower = Low SIDD (higher voltage operation, runs cooler)

    Note: a rough definition.

    Muropaketti: 87.1%
    TPU: 83.0%
    Sweclockers: 74.3%
    Nordichardware: 75.6%
    Hexus: 75.2%

    The sample Muropaketti received ran so hot that the card throttled at stock, despite the fan was running at 100% speed.

    If TPUs sample was already exceeding the PCI-E power specifications by > 11%, I wonder by how much do the highest leaking samples violate it o_O

    Also the reviewed cards (at least TPU) weren't even using prototype or ES silicon, but the very same stuff the retail cards are shipped with. This is pretty unusual since it's been a good while since I've seen a day 1 review featuring anything but ES silicon. Sometimes even the very first retail cards have ES marked silicon on them.
     
  18. Qwertilot

    Qwertilot Senior member

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    Ummm, wow. Surely they should they be testing for this sort of thing and stamping very firmly on the worst offenders?

    A bit scary to think how consoles would go with this sort of stuff.
     
  19. KTE

    KTE Senior member

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    ^Means poor process maturity and yields, currently.

    Sent from HTC 10
    (Opinions are own)
     
  20. Qwertilot

    Qwertilot Senior member

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    I guess so :)

    Just seems surprising that they're happy pushing something quite that out of spec out of the door. Is it just too expensive to test every individual chip? Maybe it is for such a relatively low GPU.
     
  21. Doom2pro

    Doom2pro Senior member

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    Are you trying to suggest that higher voltage leakage = higher operating voltage = runs cooler? Pretty sure you got the thermal parts backwards.

    Isn't it pretty common knowledge that better ASIC quality means less voltage required to operate at stable clocks due to lower voltage leakage and thus higher ASIC quality cards run cooler due to their lower operating voltage but overclock worse than less ASIC quality due to less headroom?

    The more voltage leakage the higher the operating voltage needs to be in order to compensate for the excessive voltage drop associated with lower leakage resistance and thus the higher operating temps.

    Unless you are privy to knowledge that the majority is ignorant to and you would like to share and or elaborate on further?
     
    #2071 Doom2pro, Jun 29, 2016
    Last edited: Jun 29, 2016
  22. DrMrLordX

    DrMrLordX Diamond Member

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    It isn't voltage that leaks, it's current . . .
     
  23. sm625

    sm625 Diamond Member

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    The way I interpret it is "higher voltage operation" means it is capable of reaching higher voltage at the same power/heat level.
     
  24. Abwx

    Abwx Diamond Member

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    Higher leakage means that the transistors s threshold voltage is lower, hence they conduct (leak) more when switched off but at the same time since they are closer to the conduction state a lower voltage is required to make them switch as fast (conduct the same current) as low leakage siblings.
     
  25. IEC

    IEC Lifer

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    EightySix Four on this forum has three RX 480s with ASIC scores of 70%, 77%, and 83%.

    GPU-Z BIOS dump here:
    https://1drv.ms/u/s!AqniqrcgThMVr6Io8ncCCsExJ67YZQ