Intel Core i7-11700K Review: Blasting Off with Rocket Lake
by Dr. Ian Cutress on March 5, 2021 4:30 PM EST- Posted in
- CPUs
- Intel
- 14nm
- Xe-LP
- Rocket Lake
- Cypress Cove
- i7-11700K
CPU Tests: SPEC
Page by Andrei Frumusanu
SPEC2017 is a series of standardized tests used to probe the overall performance between different systems, different architectures, different microarchitectures, and setups. The code has to be compiled, and then the results can be submitted to an online database for comparison. It covers a range of integer and floating point workloads, and can be very optimized for each CPU, so it is important to check how the benchmarks are being compiled and run.
We run the tests in a harness built through Windows Subsystem for Linux, developed by our own Andrei Frumusanu. WSL has some odd quirks, with one test not running due to a WSL fixed stack size, but for like-for-like testing is good enough. Because our scores aren’t official submissions, as per SPEC guidelines we have to declare them as internal estimates from our part.
For compilers, we use LLVM both for C/C++ and Fortan tests, and for Fortran we’re using the Flang compiler. The rationale of using LLVM over GCC is better cross-platform comparisons to platforms that have only have LLVM support and future articles where we’ll investigate this aspect more. We’re not considering closed-sourced compilers such as MSVC or ICC.
clang version 10.0.0
clang version 7.0.1 (ssh://git@github.com/flang-compiler/flang-driver.git
24bd54da5c41af04838bbe7b68f830840d47fc03)
-Ofast -fomit-frame-pointer
-march=x86-64
-mtune=core-avx2
-mfma -mavx -mavx2
Our compiler flags are straightforward, with basic –Ofast and relevant ISA switches to allow for AVX2 instructions. We decided to build our SPEC binaries on AVX2, which puts a limit on Haswell as how old we can go before the testing will fall over. This also means we don’t have AVX512 binaries, primarily because in order to get the best performance, the AVX-512 intrinsic should be packed by a proper expert, as with our AVX-512 benchmark. All of the major vendors, AMD, Intel, and Arm, all support the way in which we are testing SPEC.
To note, the requirements for the SPEC licence state that any benchmark results from SPEC have to be labeled ‘estimated’ until they are verified on the SPEC website as a meaningful representation of the expected performance. This is most often done by the big companies and OEMs to showcase performance to customers, however is quite over the top for what we do as reviewers.
For the new Cypress Cove based i7-11700K, we haven’t had quite the time to investigate the new AVX-512 instruction differences – since this is the first consumer desktop socketed CPU with the new ISA extensions it’s something we’ll revisit in the full review. Based on our testing on the server core counterparts however, it doesn’t make any noticeable differences in SPEC.
In the SPECint2017 suite, we’re seeing the new i7-11700K able to surpass its desktop predecessors across the board in terms of performance. The biggest performance leap is found in 523.xalancbmk which consists of XML processing at a large +54.4% leap versus the 10700K.
The rest of the improvements range in the +0% to +15% range, with an average total geomean advantage of +15.5% versus the 10700K. The IPC advantage should be in the +18.5% range.
In the FP scores, there’s nothing standing out too much, with general even improvements across the board. The total improvement here is +19.6%, with the IPC improvement in the +22% range.
Although the new Cypress Cove cores in the 11700K do have good generational IPC improvements, that’s all compared to the quite old predecessor, meaning that for single-thread performance, the advancements aren’t enough to quite keep up with the latest Zen3 competition from AMD, or for that matter, the Firestorm cores in Apple’s new M1.
More interesting are the multi-threaded SPEC results. Here, the new generation from Intel is showcasing a +5.8% and +16.2% performance improvement over its direct predecessor. Given the power draw increases we’ve seen this generation, those are rather unimpressive results, and actually represent a perf/W regression. AMD’s current 6-core 5600X actually is very near to the new 11700K, but consuming a fraction of the power.
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blppt - Saturday, March 13, 2021 - link
They did try to at least 'ride it out' until Zen could get done, and that required smoothing out the rough edges, so they did devote some resources.BD/PD never did any better than a low-end solution for the desktop/laptop market, but they had to offer something until Zen was done.
Oxford Guy - Sunday, March 28, 2021 - link
'They did try to at least 'ride it out' until Zen could get done, and that required smoothing out the rough edges, so they did devote some resources.'Wow... watch the goal posts move.
Riding out = doing nothing. Piledriver was not improved. The entire higher-performance & supercomputer market was unchanged from Piledriver to Zen. All AMD did was ship cheap knock-off APU rubbish and console trash.
The fact that AMD succeeded with Zen is probably mostly a testament to one largely ignored feature of monopoly power: the monopolist can become so slow and inefficient that a nearly dead competitor can come back to best it. That's not symptomatic of a well-run economic system. It's a trainwreck.
AMD should have been wealthy enough to do proper R&D and bulldozer would have never happened in the first place. But, Intel was a huge abusive monopolist and everyone went right along, content to feed the problem. After AMD did Bulldozer and Piledriver the company should have been dead. If there had been adequate competition it would have been. So, ironically, AMD can thank Intel for being its only competition, for resting on its laurels because of its extreme monopolization.
GeoffreyA - Wednesday, March 10, 2021 - link
Oxford Guy. I don't remember the exact details and am running largely from memory here. Yes, I agree, Bulldozer had far lower IPC than Phenom, but, according to their belief, was supposed to restore them to the top and knock Intel down. In practice, it failed miserably and was worse even than Netburst. Credit must be given, however, for their raising Bulldozer's IPC a lot each generation (something like 20-30% if I remember right), and curtailing power. It also addressed weaknesses in K10 and surpassed K10's IPC eventually. Anyway, working against such a hopeless design surely taught them a lot; and pouring that knowledge into a classic x86 design, Zen, took it further than Skylake after just one iteration.AMD would have done better had they just persisted with K10, which wasn't that far behind Nehalem. But, perhaps we wouldn't have had Zen: it took AMD's going through the lowest depths, passing through the fire as it were, to become what they are today, leaving Intel baffled. I agree, they were truly idiotic in the last decade but no more. May it stay that way!
Concerning CMT, I don't know much about it to comment, but think Bulldozer's principal weakness came from sharing execution units---the FP units I believe and others---between modules. Zen kept each core separate and gave it full (and weighty) resources, along with a micro-op cache and other improvements. As for Jaguar, it may be junk from a desktop point of view, yes, but was excellent in its domain and left Atom in the dust.
Oxford Guy - Sunday, March 28, 2021 - link
'Credit must be given, however, for their raising Bulldozer's IPC a lot each generation (something like 20-30% if I remember right), and curtailing power.'Piledriver was a small IPC improvement and regressed in AVX. Piledriver's AVX was so extremely poor that it was faster to not use it. Piledriver was a massive power hog. The 32nm SOI process node, according to 'TheStilt' was improved over time which is probably the main source of power efficiency improvement in Piledriver versus Bulldozer. I do not recall the IPC improvement of Piledriver over Bulldozer but it was nothing close to 20% I think. Instead, it merely made it possible to raise clocks further, along with the aforementioned node improvement. And, 'TheStilt' said the node got better after Piledriver's first generation. The 'E' parts, for instance, were quite a lot improved in leakage — but the whole line (other than the 9000 series which he said should have been sent to the scrapper) improved in leakage. What didn't improve, sadly, is the bad Piledriver design. AMD never bothered to fix it.
While Piledriver, when clocked high (like 4.7 GHz) could be relevant against Sandy in multi-thread (including well-threaded games like Desert of Kharak) it was extremely pitiful in single-thread. And, it sucked down boatloads of power to get to 4.7, even with the best-leakage chips.
And, going back to your 20–30% claim. Steamroller, which was considered a serious disappointment, featured only 4 of the CMT quasi cores, not 8. Excavator cut things in cache land even further. Both were cost-cutting parts, not performance improvements. Piledriver killed both of them simply by turning up the clocks high. The multi-thread performance of Steamroller and Excavator was not competitive because of the lack of cache, lack of cores, and lack of clock. Single-thread was a bit improved but, again, the only thing one could really do was blast current through Piledriver. It was a disgusting situation due to the single-threaded performance, which was unacceptable in 2012 and an abomination for the later years AMD kept peddling Piledriver in.
The only credit AMD deserves for the construction core period is not going out of business, despite trying so hard to do that.
GeoffreyA - Sunday, March 28, 2021 - link
Oxford Guy, while I respect your view, I do not agree with it, and still stand by my statement that AMD deserves credit for improving Bulldozer and executing yearly. Agreed, my 20-30% claim was not sober but I just meant it as a recollection and did qualify my statement.I don't think it's fair to put AMD down for embarking on Bulldozer. When they set out, quite likely they thought it was going to go further than the aging Phenom/K10 design, and the fact is, while falling behind in IPC compared with K10, it improved on a lot of points and laid the foundation. Its chief weakness was the idea of sharing resources, like the fetch, decode, and FP units, as well as going for a deeper pipeline. (The difference from Netburst is that Bulldozer was decently wide.)
Piledriver refined the foundation, raising IPC and adding a perceptron branch predictor, still used in Zen by the way, and I believe finally surpassed K10's IPC (and that of Llano). While being made on the same 32 nm process, it dropped power by switching to hard-edge flip flops, which took some work to put in. They used that lowered power to raise clock speeds, bringing power to the same level as Bulldozer. And Trinity, the Piledriver APU, surpassed Llano. I need to learn more about Steamroller and Excavator before I comment, but note in passing that SR improved the architecture again, giving each integer core its own fetch/decode units, among other things; and Excavator switched to GPU libraries in laying out the circuitry, dropping power and area, the tradeoff being lower frequency.
GeoffreyA - Sunday, March 28, 2021 - link
Also, the reviews show that things were not as bad as we remember, though power was terrible.https://www.anandtech.com/show/6396/the-vishera-re...
https://www.anandtech.com/show/5831/amd-trinity-re...
Oxford Guy - Tuesday, April 6, 2021 - link
I don't need to look at reviews agaih. I know how bad the IPC was in Bulldozer, Piledriver, Steamroller, and Excavator. Single-thread in Cinebench R15, for instance, was really low even at 5.2 GHz in Piledriver. It takes chilled water to get it to bench at that clock.GeoffreyA - Wednesday, March 10, 2021 - link
Lack of competition, high prices, lack of integrity. I agree it's one big mess, but there's so little we can do, except boycotting their products. As it stands, the best advice is likely: find a product at a decent price, buy it, be happy, and let these rotten companies do what they want.Oxford Guy - Sunday, March 28, 2021 - link
'find a product at a decent price, buy it, be happy'Buy a product you can't buy so you can prop up monopolies that cause the problem of shortage + bad pricing + low choice (features to choose from/i.e. innovation, limited).
GeoffreyA - Sunday, March 28, 2021 - link
The only solution is a worldwide boycott of their products, till they drop their prices, etc.