Intel Rocket Lake (14nm) Review: Core i9-11900K, Core i7-11700K, and Core i5-11600K
by Dr. Ian Cutress on March 30, 2021 10:03 AM EST- Posted in
- CPUs
- Intel
- LGA1200
- 11th Gen
- Rocket Lake
- Z590
- B560
- Core i9-11900K
Intel’s New Adaptive Boost Technology for Core i9-K/KF
Taken from our news item
To say that Intel’s turbo levels are complicated to understand is somewhat of an understatement. Trying to teach the difference between the turbo levels to those new to measuring processor performance is an art form in of itself. But here’s our handy guide, taken from our article on the subject.
Adaptive Boost Technology is now the fifth frequency metric Intel uses on its high-end enthusiast grade processors, and another element in Intel’s ever complex ‘Turbo’ family of features. Here’s the list, in case we forget one:
| Intel Frequency Levels | ||
| Base Frequency | - | The frequency at which the processor is guaranteed to run under warranty conditions with a power consumption no higher than the TDP rating of the processor. |
| Turbo Boost 2.0 | TB2 | When in a turbo mode, this is the defined frequency the cores will run at. TB2 varies with how many cores are being used. |
| Turbo Boost Max 3.0 | TBM3 'Favored Core' |
When in a turbo mode, for the best cores on the processor (usually one or two), these will get extra frequency when they are the only cores in use. |
| Thermally Velocity Boost | TVB | When in a turbo mode, if the peak thermal temperature detected on the processor is below a given value (70ºC on desktops), then the whole processor will get a frequency boost of +100 MHz. This follows the TB2 frequency tables depending on core loading. |
| Adaptive Boost Technology | ABT 'floating turbo' |
When in a turbo mode, if 3 or more cores are active, the processor will attempt to provide the best frequency within the power budget, regardless of the TB2 frequency table. The limit of this frequency is given by TB2 in 2-core mode. ABT overrides TVB when 3 or more cores are active. |
| *Turbo mode is limited by the turbo power level (PL2) and timing (Tau) of the system. Intel offers recommended guidelines for this, but those guidelines can be overridden (and are routinely ignored) by motherboard manufacturers. Most gaming motherboards will implement an effective ‘infinite’ turbo mode. In this mode, the peak power observed will be the PL2 value. It is worth noting that the 70ºC requirement for TVB is also often ignored, and TVB will be applied whatever the temperature. | ||
Intel provided a slide trying to describe the new ABT, however the diagram is a bit of a mess and doesn’t explain it that well. Here’s the handy AnandTech version.
First up is the Core i7-11700K that AnandTech has already reviewed. This processor has TB2, TBM3, but not TVB or ABT.
The official specifications show that when one to four cores are loaded, when in turbo mode, it will boost to 4.9 GHz. If it is under two cores, the OS will shift the threads onto the favored cores and Turbo Boost Max 3.0 will kick in for 5.0 GHz. More than four core loading will be distributed as above.
On the Core i9-11900, the non-overclocking version, we also get Thermal Velocity Boost which adds another +100 MHz onto every core max turbo, but only if the processor is below 70ºC.
We can see here that the first two cores get both TBM3 (favored core) as well as TVB, which makes those two cores give a bigger jump. In this case, if all eight cores are loaded, the turbo is 4.6 GHz, unless the CPU is under 70ºC, then we get an all-core turbo of 4.7 GHz.
Now move up to the Core i9-11900K or Core i9-11900KF, which are the only two processors with the new floating turbo / Adaptive Boost Technology. Everything beyond two cores changes and TVB no longer applies.
Here we see what looks like a 5.1 GHz all-core turbo, from three cores to eight cores loaded. This is +300 MHz above TVB when all eight cores are loaded. But the reason why I’m calling this a floating turbo is because it is opportunistic.
What this means is that, if all 8 cores are loaded, TB2 means that it will run at 4.7 GHz. If there is power budget and thermal budget, it will attempt 4.8 GHz. If there is more power budget and thermal budget available, it will go to 4.9 GHz, then 5.0 GHz, then 5.1 GHz. The frequency will float as long as it has enough of those budgets to play with, and it will increase/decrease as necessary. This is important as different instructions cause different amounts of power draw and such.
If this sounds familiar, you are not wrong. AMD does the same thing, and they call it Precision Boost 2, and it was introduced in April 2018 with Zen+. AMD applies its floating turbo to all of its processors – Intel is currently limiting floating turbo to only the Core i9-K and Core i9-KF in Core 11th Gen Rocket Lake.
One of the things that we noticed with AMD however is that this floating turbo does increase power draw, especially with AVX/AVX2 workloads. Intel is likely going to see similar increases in power draw. What might be a small saving grace here is that Intel’s frequency jumps are still limited to full 100 MHz steps, whereas AMD can do it on the 25 MHz boundary. This means that Intel has to manage larger steps, and will likely only cross that boundary if it knows it can be maintained for a fixed amount of time. It will be interesting to see if Intel gives the user the ability to change those entry/exit points for Adaptive Boost Technology.
There will be some users who are already familiar with Multi-Core Enhancement / Multi-Core Turbo. This is a feature from some motherboard vendors have, and often enable at default, which lets a processor reach an all-core turbo equal to the single core turbo. That is somewhat similar to ABT, but that was more of a fixed frequency, whereas ABT is a floating turbo design. That being said, some motherboard vendors might still have Multi-Core Enhancement as part of their design anyway, bypassing ABT.
Overall, it’s a performance plus. It makes sense for the users that can also manage the thermals. AMD caught a wind with the feature when it moved to TSMC’s 7nm. I have a feeling that Intel will have to shift to a new manufacturing node to get the best out of ABT, and then we might see the feature on the more mainstream CPUs, as well as becoming default as standard.
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Makste - Tuesday, April 6, 2021 - link
I again have to agree with you on this. Especially with the cooler scenario, it is not easy to spot the detail, but you have managed to bring it to the surface. Rocket Lake is not a good upgrade option now that I look at it.Oxford Guy - Wednesday, March 31, 2021 - link
(Sorry I messed up and forgot quotation marks in the previous post. 1st, 3rd, and 5th paragraphs are quotes from the article.)you wrote:
‘Rocket Lake on 14nm: The Best of a Bad Situation’
I fixed it:
Rocket Lake on 14nm: Intel's Obsolete Node Produces Inferior CPU'
‘Intel is promoting that the new Cypress Cove core offers ‘up to a +19%’ instruction per clock (IPC) generational improvement over the cores used in Comet Lake, which are higher frequency variants of Skylake from 2015.’
What is the performance per watt? What is the performance per decibel? How do those compare with AMD? Performance includes performance per watt and per decibel, whether Intel likes that or not.
‘Designing a mass-production silicon layout requires balancing overall die size with expected yields, expected retail costs, required profit margins, and final product performance. Intel could easily make a 20+ core processor with these Cypress Cove cores, however the die size would be too large to be economical, and perhaps the power consumption when all the cores are loaded would necessitate a severe reduction in frequency to keep the power under control. To that end, Intel finalised its design on eight cores.’
Translation: Intel wanted to maximize margin by feeding us the ‘overclocked few cores’ design paradigm, the same thing AMD did with Radeon VII. It’s a cynical strategy when one has an inferior design. Just like Radeon VII, these run hot, loud, and underperform. AMD banked on enough people irrationally wanting to buy from ‘team red’ to sell those, while its real focus was on peddling Polaris forever™ + consoles in the GPU space. Plus, AMD sells to miners with designs like that one.
‘Intel has stated that in the future it will have cores designed for multiple process nodes at the same time, and so given Rocket Lake’s efficiency at the high frequencies, doesn’t this mean the experiment has failed? I say no, because it teaches Intel a lot in how it designs its silicon’
This is bad spin. This is not an experimental project. This is product being massed produced to be sold to consumers.
Oxford Guy - Wednesday, March 31, 2021 - link
One thing many are missing, with all the debate about AVX-512, is the AVX-2 performance per watt/decibel problem:'The rated TDP is 125 W, although we saw 160 W during a regular load, 225 W peaks with an AVX2 rendering load, and 292 W peak power with an AVX-512 compute load'
Only 225 watts? How much power does AMD's stuff use with equivalent work completion speed?
Hifihedgehog - Thursday, April 1, 2021 - link
"The spin also includes the testing, using a really loud high-CFM CPU cooler in the Intel and a different quieter one on the AMD."Keep whining... You'll eventually tire out.
https://i.imgur.com/HZVC03T.png
https://i.imgflip.com/53vqce.jpg
Makste - Tuesday, April 6, 2021 - link
Isn't it too much for you to keep posting the same thing over and over?Oxford Guy - Wednesday, March 31, 2021 - link
Overclocking support page still doesn’t mention that Intel recently discontinued the overclocking warranty, something that was available since Sandy Bridge or something. Why the continued silence on this?‘On the Overclocking Enhancement side of things, this is perhaps where it gets a bit nuanced.’
How is it an ‘enhancement’ when the chips are already system-melting hot? There isn't much that's nuanced about Intel’s sudden elimination of the overclocking warranty.
‘Overall, it’s a performance plus. It makes sense for the users that can also manage the thermals. AMD caught a wind with the feature when it moved to TSMC’s 7nm. I have a feeling that Intel will have to shift to a new manufacturing node to get the best out of ABT’
It also helps when people use extremely loud very high CFM coolers for their tests. Intel pioneered the giant hidden fridge but deafness-inducing air cooling is another option.
How much performance will buyers find in the various hearing aids they'll be in the market for? There aren't any good treatments for tinnitus, btw. That's a benefit one gets for life.
‘Intel uses one published value for sustained performance, and an unpublished ‘recommended’ value for turbo performance, the latter of which is routinely ignored by motherboard manufacturers.’
It’s also routinely ignored by Intel since it peddles its deceptive TDP.
‘This is showing the full test, and we can see that the higher performance Intel processors do get the job done quicker. However, the AMD Ryzen 7 processor is still the lowest power of them all, and finishes the quickest. By our estimates, the AMD processor is twice as efficient as the Core i9 in this test.’
Is that with the super-loud very high CFM cooler on the Intel and the smaller weaker Noctua on the AMD? If so, how about a noise comparison? Performance per decibel?
‘The cooler we’re using on this test is arguably the best air cooling on the market – a 1.8 kilogram full copper ThermalRight Ultra Extreme, paired with a 170 CFM high static pressure fan from Silverstone.’
The same publication that kneecapped AMD’s Zen 1 and Zen 2 but refusing to enable XMP for RAM on the very dubious claim that most enthusiasts don’t enter BIOS to switch it on. Most people are going to have that big loud cooler? Does Intel bundle it? Does it provide a coupon? Does the manual say you need cooler from a specific list?
BushLin - Wednesday, March 31, 2021 - link
I won't argue with the rest of your assessment but given these CPUs are essentially factory overclocked close to their limits, the only people who'd benefit from an overclocking warranty are probably a handful of benchmark freaks doing suicide runs on LN2.Oxford Guy - Thursday, April 1, 2021 - link
That’s why I said the word ‘enhancement’ seems questionable.Oxford Guy - Wednesday, March 31, 2021 - link
‘Anyone wanting a new GPU has to actively pay attention to stock levels, or drive to a local store for when a delivery arrives.’You forgot the ‘pay the scalper price at retail’ part. MSI, for instance, was the first to raise its prices across the board to Ebay scalper prices and is now threatening to raise them again.
‘In a time where we have limited GPUs available, I can very much see users going all out on the CPU/memory side of the equation, perhaps spending a bit extra on the CPU, while they wait for the graphics market to come back into play. After all, who really wants to pay $1300 for an RTX 3070 right now?’
• That is the worst possible way to deal with planned obsolescence.
14nm is already obsolete. Now, you’re adding in wating for a very long time to get a GPU, making your already obsolete CPU really obsolete by the time you can get one. If you’re waiting for reasonable prices for GPUs you’re looking at, what, more than a year of waiting?
‘Intel’s Rocket Lake as a backported processor design has worked’
No. It’s a failure. The only reasons Intel will be able to sell it is because AMD is production-constrained and because there isn’t enough competition in the x86 space to force AMD to cut the pricing of the 5000 line.
Intel also cynically hobbled the CPU by starving it of cores to increase profit for itself, banking that people will buy it anyway. It’s the desktop equivalent of Radeon VII. Small die + way too high clock to ‘compensate’ + too-high price = banking on consumer foolishness to sell them (or mining, in the case of AMD). AVX-512 isn’t really going to sell these like mining sold the Radeon VII.
‘However, with the GPU market being so terrible, users could jump an extra $100 and get 50% more AMD cores.’
No mention of power consumption, heat, and noise. Just ‘cores’ and price tag.
Oxford Guy - Wednesday, March 31, 2021 - link
'Intel could easily make a 20+ core processor with these Cypress Cove cores, however the die size would be too large to be economical'Citation needed.
And, economical for Intel or the customer?
Besides, going from 8 cores to 20+ is using hyperbole to distract from the facts.
'and perhaps the power consumption when all the cores are loaded would necessitate a severe reduction in frequency to keep the power under control.'
The few cores + excessive clocks to 'compensate' strategy is a purely cynical one. It always causes inferior performance per watt. It always causes more noise.
So, Intel is not only trying to feed us its very obsolete 14nm node, it's trying to do it in the most cynical manner it can: by trying to use 8 cores as the equivalent of what it used to peddle exclusively for the desktop market: quads.
It thinks it can keep its big margins up by segmenting this much, hoping people will be fooled into thinking the bad performance per watt from too-high clocks is just because of 14nm — not because it's cranking too few cores too high to save itself a few bucks.
Intel could offer more cores and implement as turbo with a gaming mode that would keep power under control for gaming while maximizing performance. The extra cores would presumably be able to do more work for the watts by keeping clocks/voltage more within the optimal range.
But no... it would rather give people the illusion of a gaming-optimized part ('8 cores ought to be enough for anyone') when it's only optimized for its margin.