Intel Core i7-3970X Extreme Edition Processor Review

Intel Core i7-3960X has been the fastest processors for high-performance desktop systems for an entire year. But time has come for it to step down: today Intel offers Core i7-3970X Extreme Edition. Although the newcomer is hardly any different from its predecessor, we decided to subject it to detailed features and performance testing in our lab.

by Ilya Gavrichenkov
12/06/2012 | 09:39 AM

Computer enthusiasts who have preferred traditional desktop systems to the new fancy gadgets and mobile computers may have felt pretty forgotten lately. Desktop processors are slowly stepping back into secondary positions for AMD and Intel, while the companies’ primary efforts are directed towards adoption of the existing solutions for all sorts of compact systems, such as micro-servers, nettops, ultra-portable notebooks, tablets and smartphones. High performance hasn’t been the ultimate goal for the new generations of microarchitectures for a while now, with low power consumption and functional integrated graphics turning into the major determinative factors.


In this situation new desktop processors started to come out less frequently, and their performance growth slowed down substantially. Moreover, there have even been some rumors that Intel wanted to make a bold move against the untouchable feature – the possibility to upgrade by replacing the CPU in the mainboard. Does it mean that desktops are slowly dying? I don’t think so: high-performance computers will always be needed, especially since many users are eager to pay for high performance like that. We can imagine that Intel may want to introduce fully integrated non-upgradable platforms in the lower price segment, but the elite enthusiast systems will most likely still stay in their current form for a very long time.

Take, for example, the top desktop LGA 2011 platform. It has no competitors, AMD has long left this niche for good. Nevertheless, Intel continues to actively support the existing infrastructure and not only for the reasons of corporate prestige. There are most likely some good financial reasons there, too. On the one hand, the development of desktop LGA 2011 systems doesn’t require big investments: this desktop platform has the same unified design as server and workstation solutions. On the other hand, all these components are considered premium products with high revenue margins.

Intel is clearly interested in continuing with LGA 2011. This platform doesn’t just exist, but evolves rapidly. For instance, they continuously launch new processors for it, and not only when the new microarchitecture comes out. Even mainstream systems cannot boast frequent line-up refreshes like that these days, and LGA 2011 has it all. They purposefully maintain the same traditional system of values, requiring the manufacturer to show love for their users from time to time.

One of the refreshes like that is the reason for our today’s review. Intel decided to reward their enthusiastic fans favor high-performance systems and launched a new LGA 2011 processor – Core i7-3970X Extreme Edition that replaces the previous flagship CPU – Core i7-3960X, which latest in this leading role for a year. However, the new Core i7-3970X launched in a very old-fashioned manner, because in reality it is none other but a legally overclocked previous CPU model. This “new” CPU has not only the same core microarchitecture and manufacturing process, but also the same processor revision of the semiconductor die. In fact, there is no way to really increase the frequency potential of this processor that is why higher clock speed leads to higher heat dissipation and higher TDP. However, the major target group for this type of products, which typically utilizes high-end cooling solutions, will hardly be upset about it. They will be much more excited about a different aspect: how big of a performance boost it will produce and how much better the new processor will overclock. So, we will try to answer these questions to the best of our ability in the today’s review.

Closer Look at Core i7-3970X

Since the new Core i7-3970X processor is built on the exact same semiconductor die as the previous flagship LGA 2011 six-core CPU, it is fairly easy to describe the new processor in just a few short paragraphs. In fact, we are dealing with a legally overclocked Core i7-3960X, which nominal clock frequency has been increased from 3.3 GHz to 3.5 GHz, and the frequency in Turbo mode – from 3.9 GHz to 4.0 GHz. Besides the frequencies, the heat dissipation characteristics have also changed: the thermal envelope of the new Core i7-3970X is set at 150 W, while the predecessor had a TDP of only 130 W. These are the only differences between the old and the new flagship LGA 2011 processors. Just as before, the CPU is based on a 32 nm Sandy Bridge-E processor die with six computing cores, a gigantic 15 MB L3 cache and quad-channel memory controller. Besides, it also supports Hyper-Threading that enables Core i7-3970X to process up to 12 threads simultaneously.

The table below sums everything up for your convenience:

Although there are very few differences in the specifications of Core i7-3960X and Core i7-3970X, Intel could have made a few lower-level changes, but they chose not to. Just like its predecessor, the new Core i7-3970X uses C2 processor stepping with eight computing cores, two of which are disabled. You can clearly see that from the diagnostic utilities reports:

I would like to remind you that the distinguishing feature of the C2 processor stepping is the operational CT-d technology, which was originally disabled in the first LGA 2011 processors because of some implementation errors. This is exactly why they refreshed the core design a little later. So far there are no other core steppings for Sandy Bridge-E processors, so we can’t really expect any surprises from the Core i7-3970X.

Core i7-3970X Extreme Edition semiconductor die: eight-core Sandy Bridge-E with two disabled cores and inactive part of the L3 cache.

Even the increase in the typical heat dissipation is not a surprise at all. Intel has already played this card in their symmetrical Xeon E5 family, so they chose the time-tested route for the enhancement of their desktop processor line-up. In the server CPU family Intel increased only the TDP of the top eight-core Xeon E5-2687W processor. However, they believe that the desktop Core i7 do not (yet?) deserve to have eight cores. So, in our case it was solely because of the increases clock frequency.

The increase in the maximum TDP limits hardly changes anything for the flagship desktop LGA 2011 systems. The mainboards voltage regulator circuitries and LGA 2011 cooling systems have been designed for overclocking purposes right from the start. Therefore, Core i7-3970X is fully compatible even with the first-generation components, with only one exception, which is … Intel’s own RTS2011AC air-cooler, which was offered originally with LGA 2011 processors. In other words, the new Intel processor should have no compatibility issues of any kind.

Testbed Configuration and Testing Methodology

Unfortunately, over the past year while Core i7-3960X remained the top LGA 2011 contender, no other worthy challengers surfaced. So formally speaking, there is nothing to compare the new Core i7-3970X against at this time. It is undeniable that it will be the today’s fastest desktop processor, even without the tests. However, there still are a few nuances to keep in mind. Firstly, the major strength of the new Core i7-3970X is its ability to process up to twelve computing threads simultaneously, so it should demonstrate unprecedented results only in multi-threaded tasks. In more common cases, when the computing cores of this monster are not fully utilized, it could easily yield to the top LGA 1155 Core i7-3770K processor on Ivy Bridge microarchitecture that offers higher relative performance per core. Another issue with Core i7-3970X, is that the only compatible chipset, Intel X79 Express, failed to get fully certified for PCI Express 3.0. As a result, some contemporary graphics cards, such as GeForce GTX 680 and GTX 670 by default work in PCI Express 2.0 mode in LGA 2011 systems. None of the other contemporary desktop systems have issues like that.

All this indicates that it wouldn’t be fair to proclaim the LGA 2011 platform the fastest and ultimately universal solution. Therefore, we are going to compare Core i7-3970X not only against its predecessor, but also against the flagship CPUs for the other two desktop platforms – LGA 1155 and Socket AM3+.

As a result, our testbeds were configured using the following software and hardware components:


General Performance

As usual, we use Bapco SYSmark 2012 suite to estimate the processor performance in general-purpose tasks. It emulates the usage models in popular office and digital content creation and processing applications. The idea behind this test is fairly simple: it produces a single score characterizing the average computer performance. After the launch of Windows 8 SYSmark 2012 got updated to version 1.5, and this is exactly the version e are using in our test session.

As we have expected, the total performance score in general purpose tasks places Core i7-3970X on top of the charts. And it is not at all surprising that it is only 3% ahead of its predecessor - Core i7-3960X: slight increase in the clock frequency could have hardly produced a greater effect.

Let’s take a closer look at the performance scores SYSmark 2012 generates in different usage scenarios. Office Productivity scenario emulates typical office tasks, such as text editing, electronic tables processing, email and Internet surfing. This scenario uses the following applications: ABBYY FineReader Pro 10.0, Adobe Acrobat Pro 9, Adobe Flash Player 10.1, Microsoft Excel 2010, Microsoft Internet Explorer 9, Microsoft Outlook 2010, Microsoft PowerPoint 2010, Microsoft Word 2010 and WinZip Pro 14.5.

Media Creation scenario emulates the creation of a video clip using previously taken digital images and videos. Here they use popular Adobe suites: Photoshop CS5 Extended, Premiere Pro CS5 and After Effects CS5.

Web Development is a scenario emulating web-site designing. It uses the following applications: Adobe Photoshop CS5 Extended, Adobe Premiere Pro CS5, Adobe Dreamweaver CS5, Mozilla Firefox 3.6.8 and Microsoft Internet Explorer 9.

Data/Financial Analysis scenario is devoted to statistical analysis and prediction of market trends performed in Microsoft Excel 2010.

3D Modeling scenario is fully dedicated to 3D objects and rendering of static and dynamic scenes using Adobe Photoshop CS5 Extended, Autodesk 3ds Max 2011, Autodesk AutoCAD 2011 and Google SketchUp Pro 8.

The last scenario called System Management creates backups and installs software and updates. It involves several different versions of Mozilla Firefox Installer and WinZip Pro 14.5.

Overall, six-core LGA 2011 processors take the lead in specific usage scenarios. However, there are a few exceptions, when the Ivy Bridge processor design proves to be more efficient even though the top processor based on it has only four cores instead of six. Situations when larger number of cores doesn’t guarantee better performance include multi-media content processing and system management.

Gaming Performance

As you know, it is the graphics subsystem that determines the performance of the entire platform equipped with pretty high-speed processors in the majority of contemporary games. Therefore, we select the most CPU-dependent games and take the fps readings twice. The first test run is performed without antialiasing and in far not the highest screen resolutions. These settings allow us to determine how well the processors can cope with the gaming loads in general and how the tested CPUs will behave in the nearest future, when new faster graphics card models will be widely available. The second pass is performed with more real-life settings – in FullHD resolution and maximum FSAA settings. In our opinion, these results are less interesting, but they demonstrate clearly the level of performance we can expect from contemporary processors today.

We have already stated before that LGA 2011 platform can hardly be considered and ideal gaming solution. Some issues with PCI Express 3.0 support and six-core design, which contemporary games do not yet take full advantage of, make this platform less appealing for gaming needs than LGA 1155. Yes, LGA 2011 mainboards boast full support for a variety of multi-GPU graphics configurations, which doesn’t require any additional hubs, but not everyone will really appreciate this feature. In a more general case, as we can see, the system with Core i7-3770K inside can do at least as well as a system with the new Core i7-3970X in FullHD resolution with maximum image quality settings. However, this LGA 1155 system will be significantly more affordable. Although, we can’t disregard immense potential of the LGA 2011 system here. If the graphics sub-system is not the limiting factor, and the game knows to create numerous parallel threads, then Core i7-3970X becomes an indisputable leader.

Performance in Applications

To test the processors performance during data archiving we resort to WinRAR archiving utility. Using maximum compression rate we archive a folder with multiple files with 1.1 GB total size.

WinRAR version 4.2 has been significantly optimized for multi-threading that is why six-core LGA 2011 processors do very well here. Namely, the new Core i7-3970X outperforms Core i7-3770K by almost 25%.

The processor performance in cryptographic tasks is measured using a built-in benchmark of the popular TrueCrypt utility that uses AES-Twofish-Serpent “triple” encryption. I have to say that this utility not only loads any number of cores with work in a very efficient manner, but also supports special AES instructions.

Cryptographic tasks run great on eight-core AMD processors, but the six-core Core i7-3970X easily shows FX-8350 its place. AMD processors can in most cases compete against Intel’s quad-core offerings, but under no circumstances can they get even remotely close to the performance level of six-core CPUs.

We use Apple iTunes utility to test audio transcoding speed. During this test we transcode the contents of a CD disk into AAC format. Note that the peculiarity of this program is the exclusive single-threaded load.

This pretty interesting iTunes test reveals a few weaknesses of the Sandy Bridge-E design. Though the new Core i7-3970X has become 2.5% faster than the predecessor, it falls behind Core i7-3770K. This is exactly the case when Ivy Bridge microarchitecture demonstrates better relative performance, which we mentioned above.

Now that the eighth version of the popular scientific Mathematica suite is available, we decided to bring it back as one of our regular benchmarks. We use MathematicaMark8 integrated into this suite to test the systems performance:

However, higher frequency does matter for the new Core i7-3970X in Mathematica 8, where it takes the lead again.

We measured the performance in Adobe Photoshop CS6 using our own benchmark made from Retouch Artists Photoshop Speed Test that has been creatively modified. It includes typical editing of four 24-megapixel images from a digital photo camera.

Do not think that processors like Core i7-3970X need special multi-threaded environment. Even if the application doesn’t fully utilize all the processor cores, the processor still performs very well. This is where Turbo Boost steps in and increases its clock frequency to 4.0 GHz under loads with fewer threads. As a result, even if we run the Photoshop tests without applying any of the resource-hungry filters to the images, but during typical diverse processing tasks, the flagship LGA 2011 CPU will show unattainably high performance number anyway.

We have also performed some tests in Adobe Photoshop Lightroom 4.2 program. The test scenario includes post-processing and export into JPEG format of two hundred 12-megapixel images in RAW format.

Adobe Lightroom knows how to process photographs using multiple threads, which is Core i7-3970X friendly environment. It proves to be 2.5% faster than its predecessor and leaves Core i7-3770K 13% behind.

The performance in Adobe Premiere Pro CS6 is determined by the time it takes to render a Blu-ray project with a HDV 1080p25 video into H.264 format and apply different special effects to it.

High definition video content processing is one of the best types of load for multi-core processors. Therefore, systems with top LGA 2011 CPUs will be a great choice for those who work with HD content a lot. For example, the new Core i7-3970X is as ,much as 32% faster in premiere Pro CS5 than the flagship LGA 1155 system.

In order to measure how fast our testing participants can transcode a video into H.264 format we used x264 HD Benchmark 5.0. It works with an original MPEG-2 video recorded in 1080p resolution with 20 Mbps bitrate. I have to say that the results of this test are of great practical value, because the x264 codec is also part of numerous popular transcoding utilities, such as HandBrake, MeGUI, VirtualDub, etc.

The results obtained during video transcoding tests are very similar to what we have already SEEN IN Premiere Pro. Core i7-3970X is 30% faster than the top processors in any of the alternative platforms.

We will test computational performance and rendering speeds in Autodesk 3ds max 2011 using the special SPECapc for 3ds max 2011 benchmark:

Rendering is yet another example of a multi-threaded task, where Intel’s $1000 processors prove totally worth the price. Professional users should be highly pleased with all of them: Core i7-3970X, just like its predecessor, will be a great choice for a pretty fast workstation. The only possible alternative in this case would be a dual-processor Xeon E5 based system, for example.

Power Consumption

We could have easily predicted that the new Core i7-3970X will have higher performance than its predecessor by just looking at its clock frequency. However, its higher thermal parameters make this testing a little bit more intriguing. Intel pushed the TDP back by 20 W, but we have some doubts that this is true to life. In fact, the clock frequency didn’t increase far enough to cause a 15% heat dissipation spike. Besides, the voltage intervals on the new LGA 2011 processors didn’t change a bit. In other words, we do expect some power consumption increase, but doubt that the new Core i7-3970X will consume 20 W more power under load than Core i7-3960X.

To find out more about the power consumption of all current processor models in the new AMD FX family, we performed a round of special tests. The new digital power supply unit from Corsair – AX1200i – allows monitoring consumed and produced electrical power, which we use actively during our power consumption tests. The graphs below (unless specified otherwise) show the full power draw of the computer (without the monitor) measured after the power supply. It is the total power consumption of all the system components. The PSU's efficiency is not taken into account. The CPUs are loaded by running the 64-bit version of LinX 0.6.4-AVX utility. Moreover, we enabled Turbo mode and all power-saving technologies to correctly measure computer's power draw in idle mode: C1E, C6, Enhanced Intel SpeedStep and AMD Cool’n’Quiet.

In idle mode all processors and platforms usually consume about the same power. However, in case of LGA 2011 platform this rule doesn’t quite stick. It looks like the more complex system structure including a quad-channel memory controller and a PCI Express bus controller supporting up to 40 lanes, may have affected the power consumption levels. As a result, the power appetites of systems with Core i7-3970X and Core i7-3960X in idle mode are about 20 W higher than those of simpler LGA 1155 and Socket AM3+ configurations.

Single-threaded load also shows higher power consumption levels for LGA 2011 systems. Both six-core CPUs from Intel consume even more than an eight-core AMD processor, which usually is the more power-hungry contemporary processor. However, Intel’s Sandy Bridge-E design is not cut for energy-efficiency either. Moreover, when the new processor boosts its frequency to 4.0 GHz in case of single-threaded load, it even sets the new power consumption “record” leaving its predecessor noticeably behind.

Of course, if you feel like shocking anyone with your power consumption numbers, then maximum load is the way to go. This is where Core i7-3970X is the one and only leader. Its power consumption is so high that it not only puts the system with AMD FX-8350 to shame, but also more than doubles the power readings of the LGA 1155 configuration with a Core i7-3770K. However, the power consumption difference between the system with the new Core i7-3970X and the system with the Core i7-3960X still doesn’t reach 20 W – only 12 W. In other words, the newly declared TDP have some reserves for yet another frequency boost allowing for even faster six-core Sandy Bridge-E processor to come out one day.


There is an opinion that increased nominal clock frequency of the new processor should result into a higher overclocking potential. It is often true, but things are totally different with Core i7-3970X. As we have already seen, this processor has been created by “legally” overclocking the previous CPU model and doesn’t have anything new in its semiconductor core. It uses the same exact stepping of the 23 nm core as Core i7-3960X, and its clock speed increased together with the TDP. In other words, Core i7-3970X should overclock in exactly the same manner as Core i7-3960X.

But in reality, this isn’t bad at all. Core i7-3960X overclocked well, and the same is true for Core i7-3970X. Both these processors belong to Extreme Edition series, which means that they have unlocked clock frequency multipliers, i.e. allow settings the clock frequency without changing the BCLK frequency. However, the LGA 2011 platform allows adjusting the clock generator frequency in the 100-125 MHz interval without any loss of system stability. So, overclockers have a lot of freedom to experiment. Nevertheless, it is not very good to change the BCLK frequency during Core i7-3970X overclocking: it won’t provide any additional performance boost, but will simply offer a different route to adjusting the CPU clock. Therefore, we chose to overclock our test processor by simply manipulating its clock frequency multiplier.

So, the goal of our experiments was to determine the frequency, at which Core i7-3970X would be able to continuously operate in 24/7 mode without losing stability. Therefore, we didn’t use any potentially dangerous voltage settings and worked with NZXT Havik 140 air-cooler. After that we tested our overclocked system stability by running OCCT 4.3.2 utility (30-minute test in Large Data Set mode).

Our Core i7-3970X remained stable at the maximum frequency of 4.6 GHz. The CPU Vcore in this case was set at 1.375 V and Load-Line Calibration function was enabled.

I have to say that maximum acceptable temperature for Core i7-3970X cores is the same as before - 91°C. After that the processor’s thermal throttling kicks in. therefore, it is important to choose a cooling system with proper efficiency and the use of more efficient systems may actually further improve the overclocking results. In our specific case, the temperatures were 5-10°C below the critical maximum at all times.

All obtained results indicate that Core i7-3970X overclocks the same way as its predecessor. We have already reached 4.6 GHz frequency before – this is typical overclocking level for any Sandy Bridge-E processors with C2 stepping under an efficient air-cooler. In other words, the new Intel processor doesn’t really offer anything new to overclockers in this respect.


I have to admit that the new Intel Core i7-3970X Extreme Edition processor is somewhat boring. And there are two reasons for that. First, there is nothing principally new about it. All we have is simply a manufacturer-overclocked previous flagship CPU model. It results in a pretty expect performance boost of 2-4%, slight increase in the power consumption and no real improvement in the overclocking potential. Second, the top LGA 2011 processors do not have any real competitors. In case of heavy multi-threaded load these six-core monsters leave all LGA 1155 as well as Socket AM3+ processors very far behind.

However, no one promised us anything magical here. The launch of Core i7-3970X Extreme Edition is more of an image move. Intel simply reminded us of the LGA 2011 platform and the fact that it is today’s fastest desktop configuration available. Of course, the existing LGA 2011 users will not rush after the new CPU, because it won’t offer them anything new. However, it may appeal to those who are in the process of building a new high-performance desktop targeted for resource-demanding professional tasks among other things, but who haven’t yet joined the LGA 2011 eco-system. If you are one of those users, we have great news: Core i7-3970X comes at a standard price for Intel’s flagship processors of $1000, so it makes absolutely no sense to even consider Core i7-3960X at this point.

At the same time, the launch of the new Core i7-3970X also gives us cause for concern. This CPU still uses the old 32 nm Sandy Bridge-E design, while the low-end and mainstream users have long been able to enjoy the new Ivy Bridge microarchitecture and more energy-efficient 22 nm semiconductor devices. As we see, Intel is not in any hurry to share their innovations with the flagship platform. The recent launch of the Core i7-3970X indicates that it will still be a while before we see new advanced six-core Ivy Bridge-E LGA 2011 processors.