Precision Boost 2

Exact per-core turbo timings for the new processors will be determined by AMD’s voltage-frequency scaling functionality through Precision Boost 2. This feature, which we covered extensively in our Ryzen 7 2700X review, relies on available power and current to determine frequency, rather than a discrete look-up-table for voltage and frequency based on loading. Depending on the system default capabilities, the frequency and voltage will dynamically shift in order to use more of the power budget available at any point in the processor loading.

The idea is that the processor can use more of the power budget available to it than a fixed look up table that has to be consistent between all SKUs that are stamped with that number.

Precision Boost 2 also works in conjunction with XFR2 (eXtreme Frequency Range) which reacts to additional thermal headroom. If there is additional thermal budget, driven by a top-line cooler, then the processor is enabled to use more power up to the thermal limit and get additional frequency. AMD claims that a good cooler in a low ambient situation can compute >10% better in selected tests as a result of XFR2.

Ultimately this makes testing Threadripper 2 somewhat difficult. With a turbo table, performance is fixed between the different performance characteristics of each bit of silicon, making power the only differentiator. With PB2 and XF2, no two processors will perform the same. AMD has also hit a bit of a snag with these features, choosing to launch Threadripper 2 during the middle of a heatwave in Europe. Europe is famed for its lack of air conditioning everywhere, and when the ambient temperature is going above 30ºC, this will limit additional performance gains. It means that a review from a Nordic publication might see better results than one from the tropics, quite substantially.

Luckily for us we tested most of our benchmarks while in an air conditioned hotel thanks to Intel’s Data-Centric Innovation Summit which was the week before launch.

Precision Boost Overdrive

The new processors also support a feature called Precision Boost Overdrive, which looks at three key areas for power, thermal design current, and electrical design current. If any of these three areas has additional headroom, then the system will attempt to raise both the frequency and the voltage for increased performance. PBO is a mix of ‘standard’ overclocking, giving an all core boost, but gives a single core frequency uplift along with the support to still keep Precision Boost trying to raise frequency in middle-sized workloads, which is typically lost with a standard overclock. PBO also allows for idle power saving with a standard performance. PBO is enabled through Ryzen Master.

The three key areas are defined by AMD as follows:

  • Package (CPU) Power, or PPT: Allowed socket power consumption permitted across the voltage rails supplying the socket
  • Thermal Design Current, or TDC: The maximum current that can be delivered by the motherboard voltage regulator after warming to a steady-state temperature
  • Electrical Design Current, or EDC: The maximum current that can be delivered by the motherboard voltage regulator in a peak/spike condition

By extending these limits, PBO gives rise for PB2 to have more headroom, letting PB2 push the system harder and further. PBO is quoted by AMD as supplying up to +16% performance beyond the standard.

AMD also clarifies that PBO is pushing the processor beyond the rated specifications and is an overclock: and thus any damage incurred will not be protected by warranty


Also available with the new Ryzen Threadripper 2 processors is StoreMI, AMD’s solution to caching by offering configurable tiered storage for users that want to mix DRAM, SSD, and HDD storage into a single unified platform. The software implementation dynamically adjusts data between up to 2GB of DRAM, up to 256 GB of SSD (NVMe or SATA), and a spinning hard drive to afford the best reading and writing experience when there isn’t enough fast storage.

AMD initially offered this software as a $20 add-on to the Ryzen APU platform, then it became free (up to a 256GB SSD) for the Ryzen 2000-series processors. That offer now extends to Threadripper. AMD’s best case scenario is citing a 90% improvement in loading times.

Core to Core to Core: Design Trade Offs Feed Me: Infinity Fabric Requires More Power
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  • ibnmadhi - Monday, August 13, 2018 - link

    It's over, Intel is finished.
  • milkod2001 - Monday, August 13, 2018 - link

    Unfortunately not even close. Intel was dominating for last decade or so. Now when AMD is back in game, many will consider AMD but most will still get Intel instead. Damage was done.It took forever to AMD to recover from being useless and will take at least 5 years till it will get some serious market share. Better late than never though...
  • tipoo - Monday, August 13, 2018 - link

    It's not imminent, but Intel sure seems set for a gradual decline. It's hard to eke out IPC wins these days so it'll be hard to shake AMD off per-core, they no longer have a massive process lead to lead on core count with their margins either, and ARM is also chipping away at the bottom.

    Intel will probably be a vampire that lives another hundred years, but it'll go from the 900lb gorilla to one on a decent diet.
  • ACE76 - Monday, August 13, 2018 - link

    AMD retail sales are equal to Intel now...and they are starting to make a noticeable dent in the server market as won't take 5 years for them to be on top...if Ryzen 2 delivers a 25% increase in performance, they will topple Intel in 2019/2020
  • HStewart - Monday, August 13, 2018 - link

    "AMD retail sales are equal to Intel now"

    Desktop maybe - but that is minimal market.
  • monglerbongler - Monday, August 13, 2018 - link

    Pretty much this.

    No one really cares about workstation/prosumer/gaming PC market. Its almost certainly the smallest measurable segment of the industry.

    As far as these companies' business models are concerned:

    Data center/server/cluster > OEM consumer (dell, hp, microsoft, apple, asus, toshiba, etc.) > random categories like industrial or compact PCs used in hospitals and places like that > Workstation/prosumer/gaming

    AMD's entire strategy is to desperately push as hard as they can into the bulwark of Intel's cloud/server/data center dominance.

    Though, to be completely honest, for that segment they really only offer pure core count and PCIe as benefits. Sure they have lots of memory channels, but server/data center and cluster are already moving toward the future of storage/memory fusion (eg Optane), so that entire traditional design may start to change radically soon.

    All important: Performance per unit of area inside of a box, and performance per watt? Not the greatest.

    That is exceptionally important for small companies that buy cooling from the power grid (air conditioning). If you are a big company in Washington and buy your cooling via river water, you might have to invest in upgrades to your cooling system.

    Beyond all that the Epyc chips are so freaking massive that they can literally restrict the ability to design 2 slot server configuration motherboards that also have to house additional compute hardware (eg GPGPU or FPGA boards). I laugh at the prospect of a 4 slot epyc motherboard. The thing will be the size of a goddamn desk. Literally a "desktop" sized motherboard.

    If you cant figure it out, its obvious:

    Everything except for the last category involves massive years-spanning contracts for massive orders of hundreds of thousands or millions of individual components.

    You can't bet hundreds of millions or billions in R&D, plus the years-spanning billion dollar contracts with Global Foundries (AMD) or the tooling required to upgrade and maintain equipment (Intel) on the vagaries of consumers, small businesses that make workstations to order, that small fraction of people who buy workstations from OEMs, etc.

    Even if you go to a place like Pixar studios or a game developer, most of the actual physical computers inside are regular, bone standard, consumer-level hardware PCs, not workstation level equipment. There certainly ARE workstations, but they are a minority of the capital equipment inside such places.

    Ultimately that is why, despite all the press, despite sending out expensive test samples to Anandtech, despite flashy powerpoint presentations given by arbitrary VPs of engineering or CEOs, all of the workstation/Prosumer/gaming stuff is just low-binned server equipment.

    because those are really the only 2 categories of products they make;

    pure consumer, pure workstation. Everything else is just partially enabled/disabled variations on those 2 flavors.
  • Icehawk - Monday, August 13, 2018 - link

    I was looking at some new boxes for work and our main vendors offer little if anything AMD either for server roles or desktop. Even if they did it's an uphill battle to push a "2nd tier" vendor (AMD is not but are perceived that way by some) to management.
  • PixyMisa - Tuesday, August 14, 2018 - link

    There aren't any 4-socket EPYC servers because the interconnect only allows for two sockets. The fact that it might be difficult to build such servers is irrelevant because it's impossible.
  • leexgx - Thursday, August 16, 2018 - link

    is more then 2 sockets needed when you have so many cores to play with
  • Relic74 - Wednesday, August 29, 2018 - link

    Actually there are, kind of, supermicro for example has created a 4 node server for the Epyc. Basically it's 4 computers in one server case but the performance is equal to that if not better than that of a hardware 4 socket server. Cool stuff, you should check it out. In fact, I think this is the way of the future and multi socket systems are on their way out as this solution provides more control over what CPU. As well as what the individual cores are doing and provides better power management as you can shut down individual nodes or put them in stand by where as server with 4 sockets/CPU's is basically always on.

    There is a really great white paper on the subject that came out of AMD, where the stated that they looked into creating a 4 socket CPU and motherboard capable of handling all of the PCI lanes needed, however it didn't make any sense for them to do so as there weren't any performance gains over the node solution.

    In fact I believe we will see a resurrection of blade systems using AMD CPU's, especially now with all of the improvements that have been made with multi node cluster computing over the last few years.

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