The AMD 2nd Gen Ryzen Deep Dive: The 2700X, 2700, 2600X, and 2600 Tested
by Ian Cutress on April 19, 2018 9:00 AM ESTPrecision Boost 2 and XFR2: Ensuring It Hertz More
One of the biggest changes for the new Ryzen-2000 series is in how the processor implements its turbo. Up until this point (except the recent APU launch), processors have relied on a step function implementation: the system determines how many threads are loaded, attempts to implement a specific frequency on those cores if possible, and then follows the look-up table relating thread count to frequency. AMD’s goal in Precision Boost 2 is to make this process more dynamic.
This image from AMD is how the feature is being represented: the system will determine how much of the power budget is still available, and turbo as much as possible until it hits one of the limiting factors. These factors can be any of, but not limited to, the following:
- Total chip peak power
- Individual core voltage/frequency response
- Thermal interactions between neighboring cores
- Power delivery limitations to individual cores/groups of cores
- Overall thermal performance
AMD’s new Ryzen Master 1.3 software, when used on a Ryzen 2000-series processor, has several indicators to determine what the limiting factors are. For the most part, the way the processor will boost and respond to the environment, will be transparent to the user.
The best way to test this in action, from my perspective, is to look at the power draw of the first generation and second generation Ryzen processors. We can examine the internal estimated power consumption of each core individually as thankfully AMD has left these registers exposed, to give the following data:
This is only the core consumption power, not the package power, which would include the DRAM controller, the Infinity Fabric, and the processor IO. This means we get numbers different to the rated TDP, but the danger here is that because the Ryzen 7 2700X has a 10W TDP higher than the Ryzen 7 1800X, where the 2700X draws more power it could seem as if that is the TDP response.
Just plotting the power consumption gives this graph:
Even in this case it is clear that the Ryzen 7 2700X is drawing more power, up to 20W more, for a variable threaded load. If we change the graph to be a function of peak power:
The results are not quite as clear: it would seem that the 1800X draws, as a percentage of peak power, more at low thread count, but the 2700X draws more at a middling thread count.
It is worth noting that the end result of Precision Boost 2 is two-fold: more performance, but also more power consumption. Users looking to place one of the lower powered processors into a small form factor system might look at disabling this feature and returning to a standard step-function response in order to keep the thermal capabilities in check.
A side note – despite the marketing name being called ‘Precision Boost 2’, the internal BIOS name is called ‘Core Performance Boost’. It sounds similar to Multi-Core Enhancement, which is a feature on some Intel motherboards designed to go above and beyond the turbo mechanism. However, this is just AMD’s standard PB2: disabling it will disable PB2. Initially we turned it off, thinking it was a motherboard manufacturer tool, only to throw away some testing because there is this odd disconnect between AMD’s engineers and AMD’s marketing.
Extended Frequency Range 2 (XFR2)
For the Ryzen 2000-series, AMD has changed what XFR does. In the previous generation it was applied on certain processors to allow them to boost above the maximum turbo frequency when the thermal situation was conducive to higher frequencies and higher voltage in low thread-count states. For this generation, it still relates to thermals, however the definition is applied to any core loading: if the CPU is under 60ºC, the processor can boost no matter what the loading is above its Precision Boost 2 frequency (so why not get a better PB2 implementation?). The core still has to be within a suitable voltage/frequency window to retain stability, however.
On certain motherboards, like the ASUS Crosshair VII Hero, there are additional options to assist XFR2 beyond AMD’s implementation. ASUS does not go into specific details, however I suspect it implements a more aggressive version, perhaps extending the voltage/frequency curve, raising the power limits, and/or adjusting the thermal limit.
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danjw - Friday, April 20, 2018 - link
They Anandtech used the rated speeds that the processors were stated to support by the manufactures. Anandtech, is using everything at stock. Anandtech ran all the processors through fully patched systems (both bios and OS). Not every website other tests to these same methodology. So, there will be differences in their results. None the less, Anandtech, is auditing their results to double check them. I really don't think they are going to see anything wrong. Toms, ran their Intel parts without the latest bios updates. Others overclocked their systems.Most users do not overclock their systems. Sure, a lot of us readers do, but not everyone. I overclock my systems, but, my two brothers who are both just as technical as I am, do not. It is a choice some make and others do not. The majority of users do not overclock. So, Anandtech does not overclock in their most reviews. They have at times in the past and may in the future include overclocking results in reviews, but they have are always broken out the overclocking results in a separate section and/or labeled the overclocked results to differentiate them from the standard clocked results. These are editorial choices that Anandtech makes, I don't see any problem with that.
Luckz - Monday, April 23, 2018 - link
Intel for some reason have 4 memory sticks. Weird idea.werpu - Friday, April 20, 2018 - link
Well the main difference is they tested against fully meltdown and specte patched systems, which in fact is the norm, while all other reviewers simply tested against bare metal. It is known that Intel took a pretty serious hit especially with Meltdown and a more serious hit with Spectre compared to AMD which did not have meltdown at all and to a lesser degree Spectre than Intel did.I would say Anandtechs tests are spot on.
And this reflects the sad state of nowadays performance testing which seems to be done to 99.9% by incompetent idiots or fanboys (especially the youtubers are the worst)
However in extreme situations Intel again wins since the 8700k can be oced by decapping and good cooling to 5GHz while the OC capabilities of the 2700x are basically non existent. It really depends, which is better. But the performance gap is closing and in non OCed system it is not existent anymore. It will be interesting next year when AMD has moved to 7nm while Intel still will be stuck at 10nm which they currently try to pull it but not have yet managed. Then the game might be entirely reversed.
Alphasoldier - Friday, April 20, 2018 - link
Unfortunatelly, you are the only idiot and fanboy here. Pretty much everyone stated in their reviews, the system were fully patched, all cpus were reused and everything was retested, because AMD fanboys were screaming Meltdown here, Spectre there.Now, the internet is full of this garbage review, it spreads like cancer, because AMD fanboys have nothing better to do, once again they are disappointed that 6 cores from Intel outperformed 8 cores from AMD and they are now like the Liverpool fans repeating "The next year will be ours"
But at least they got some fancy RBG cooler.
Fallen Kell - Friday, April 20, 2018 - link
Alphasoldier, I've been reading the reviews, and while many have stated they have applied the software (OS) patches, very few have stated they applied both the software and BIOS patches for the Spectre variant 2. Thew few places that I have seen which have stated both the software and BIOS patches were applied all seem to be showing much more similar results as the AT article.In anycase, Ryan stated they are looking into it, and I am certain we will see an update within the next few days. And don't come saying that I am a AMD fanboi, I havn't purchased a AMD CPU since the Thunderbird (i.e. a slot A CPU).
mapesdhs - Saturday, April 21, 2018 - link
werpu, oc an 8700K to 5GHz? Makes me laugh that a 300MHz bump over a CPU's max single core turbo is even called an oc these days. Sheesh, it's a far cry from the days of SB, oc hardly seems worth bothering with now.mkaibear - Thursday, April 19, 2018 - link
It's here, it's here!Dr. Swag - Thursday, April 19, 2018 - link
What is with the gaming benchmarks? On your tests the whole ryzen 2 series is a step above everything else, but all other reviews show it between ryzen and coffee lake...fallaha56 - Thursday, April 19, 2018 - link
This is the Spectre2 patch effectNot looking great for Intel and HFR gaming
Ryan Smith - Thursday, April 19, 2018 - link
"What is with the gaming benchmarks?"We're looking into it right now. Some of these results weren't in until very recently, so we're going back and doing some additional validation and logging to see if we can get to the bottom of this.