Intel Core i7-7700K Kaby Lake Processor Review

Introduction

The Intel Core i7-6700K has become a firm favourite among PC enthusiasts despite the performance improvements being fairly slim compared to the previous generation, Intel hasn’t been under any pressure to go beyond the status quo and introduce models outside of the HEDT platform with extra cores. Evidently, the company has fixated on power efficiency savings instead of a revolutionary step forward in instructions per clock. To be fair, the lack of competition from AMD allowed Intel to adopt a more conservative approach and their products still dominate the market. As a result, the i7-6700K’s pricing left a lot to be desired and often hovered around the £320-£350 price bracket. Thankfully, the situation is changing and AMD’s upcoming AM4 platform could instigate a pricing war and make AMD processors a viable option once again.

Intel’s Core i7-7700K is designed to replace the existing i7-6700K and employs an identical 91W TDP as well as a 4-core, 8-thread configuration. This time, the base frequency has been bumped up from 4.0GHz to 4.2GHz while the turbo extends from 4.2GHz to 4.5GHz. As you might expect, the same amount of level 3 cache is deployed and there’s backwards compatibility with existing Z170 motherboards providing the latest BIOS has been flashed. Interestingly, the official memory support is DDR4-2400 although this isn’t that important since DIMMs have much faster XMP profiles. The only other change is the Z270 platform’s 24 PCI-E x16 Gen 3 lanes which support more connectivity protocols including USB 3.1 Type-C, Thunderbolt and U.2. After the long wait, is Intel’s new enthusiast CPU worth buying? Let’s find out!

Specification

What’s New?

The company’s 7th generation CPU series codenamed Kaby Lake doesn’t follow the usual Tick-Tock release cycle. Previously, Intel would perform a die shrink and enact an architecture change before refining the process to enable better performance. In a disappointing turn of events, Kaby Lake is simply a default frequency boost which is made possible thanks to the 14nm+ manufacturing process. According to Intel, the improved fin profile, transistor channel strain and integrated design are enough to provide greater stability and uphold the higher 4.5GHz turbo clock.

On another note, Kaby Lake is the first processor range to support Intel’s Optane technology which is a premium form of non-volatile memory. Essentially, this allows Kaby Lake owners to access affordable, high-density memory offering speeds up to 1000 times faster than NAND. Not only that, the 3D XPoint design can utilise 10 times the capacity of DRAM within the same surface area. The system works by slicing submicroscopic layers of materials into columns which contain memory cells. Then, the layers connect using an innovative cross point structure of perpendicular wires. The Optane technology has an extremely low latency measured in nanoseconds which could revolutionise computing in the near future. Also, the non-volatile memory can retrieve data even after a power outage.

The latest Intel Graphics HD 630 introduces support for VP9 decoding and 4K HEVC 10-bit decode/encode. Of course, there’s still 1080p HEVC decode/encode which became an integral part of Skylake’s video functionality. Apparently, Kaby Lake can decode 4K-resolution content at 60 frames-per-second with a bit-rate up to 120Mbps. The architecture has native support for HDCP 2.2 and Microsoft PlayReady 3.0. Therefore, it’s possible to view 4K Netflix streams through the Edge web browser on a Kaby Lake processor. The iGPU has some minor improvements when it comes to gaming although it’s still pretty weak in comparison to discrete solutions.

DISCLAIMER: This is a retail CPU that was not provided or supplied by Intel Corporation. Therefore, as we have no NDA with Intel, we are available to publish any content we see fitting.

Test System and Methods

Here is the full range of test systems used for CPU and APU reviews:

Test System

Z87

• Motherboard – ASUS Maximus VII Ranger
• RAM – 16GB Crucial Ballistix Sport XT (2 x 8GB) DDR3 1866MHz (10-10-10-30)
• CPU Cooler – Thermaltake Water 3.0 with Gelid GC-Extreme
• Graphics Card – Gigabyte G1 Gaming GTX 980Ti
• Power Supply – BeQuiet Dark Power Pro 850 Watt
• Main Storage Drive – Toshiba OCZ VX500 500GB
• Chassis – Lian Li T80 Test Bench
• Displays – U2868PQU 4K
• Operating System – Windows 10 Pro 64 Bit

Z170

• Motherboard – ASRock Z170 Extreme7+
• RAM – Crucial Ballistix Elite 16GB (2x8GB) 2666MHz (16-17-17)
• CPU Cooler – Thermaltake Water 3.0 with Gelid GC-Extreme
• Graphics Card – Gigabyte G1 Gaming GTX 980Ti
• Power Supply – BeQuiet Dark Power Pro 850 Watt
• Main Storage Drive – Toshiba OCZ VX500 500GB
• Chassis – Lian Li T80 Test Bench
• Displays – U2868PQU 4K
• Operating System – Windows 10 Pro 64 Bit

Z270

• Motherboard – Combination used to determine widespread performance
• RAM – Crucial Ballistix Elite 16GB (2x8GB) 2666MHz (16-17-17)
• CPU Cooler – Thermaltake Water 3.0 with Gelid GC-Extreme
• Graphics Card – Gigabyte G1 Gaming GTX 980Ti
• Power Supply – BeQuiet Dark Power Pro 850 Watt
• Main Storage Drive – Toshiba OCZ VX500 500GB
• Chassis – Lian Li T80 Test Bench
• Displays – U2868PQU 4K
• Operating System – Windows 10 Pro 64 Bit

X99

• Motherboard – ASUS ROG STRIX X99 GAMING
• RAM – 32GB Crucial Ballistix Sport (4x8GB) 2400MHz (16-16-16-39)
• CPU Cooler – Thermaltake Water 3.0 with Gelid GC-Extreme
• Graphics Card – Gigabyte G1 Gaming GTX 980Ti
• Power Supply – BeQuiet Dark Power Pro 850 Watt
• Main Storage Drive – Toshiba OCZ VX500 500GB
• Chassis – Lian Li T80 Test Bench
• Displays – U2868PQU 4K
• Operating System – Windows 10 Pro 64 Bit

Games Used

• Ashes of the Singularity (DirectX 12)
• Dirt Rally
• Rise of the Tomb Raider (DirectX 12)
• Shadow of Mordor
• Tomb Raider

Test Software

• 3DMark – available here
• AIDA64 Engineer – available here
• Cinebench – available here
• CPUID HWMonitor – available here
• CPU-Z – available here
• Handbrake – available here
• Prime95 – available here
• WinRAR – available here
• WPrime – available here

Test Procedure 

Here at eTeknix, we endeavour to disclose key information regarding the benchmarking process so that readers can quantify the results and attempt to replicate them using their own hardware. When it comes to CPU reviews, the benchmarks are pretty self-explanatory although there are a few exceptions. Please note, we prefer to re-test each CPU within a product’s performance range to ensure the results are completely accurate and reflect any changes to our samples over time or enhancements via graphics drivers.

This means we now include fewer results, but they are more accurate and easier to decipher. As always, your choice of motherboard, the silicon lottery and other factors can yield different numbers and there’s always a margin for error when using software. Therefore, your experience may vary. Saying that, each benchmark is run at least three times and the average figure is taken to try to reduce the effect of hardware variation. Any important details regarding the benchmarks will be listed below.

Handbrake

To stress processors to their absolute limit and accurately judge performance in video editing workloads, we transcode a 7.7GB compilation of gaming footage. This particular file is freely available from here. The captured footage is 22 minutes and 12 seconds long, has a bit rate of 50.1 Mbps and uses the Advanced Video Codec. Additionally, the video runs at a constant 30 frames-per-second and opts for a 3820×2140 (4K) resolution. Once loaded into Handbrake, we transcode the 4K MP4 to a 1080p MKV file.

CPU Benchmarks – Ashes of the Singularity, Cinebench, Handbrake, WPrime and WinRAR

Ashes of the Singularity

Ashes of the Singularity’s dedicated CPU benchmark can take advantage of those extra cores and poses a problem for even the most expensive options on the market such as the i7-6950X. At stock values, the i7-7700K records a commendable result which defeats its predecessor and has a good lead over the 6-core i7-5820K. Once overclocked to 5.1GHz, the frame-rate increases by a decent amount and allows the CPU to stay within touching distance of the i7-5960X running at the default turbo frequency. This is a significantly better result than I expected, although the substantial gains may be down to a margin of error.

Cinebench R15

Prior to overclocking, the Intel i7-7700K falls just short of a 1000 multi-threaded score and remains well above the i7-6700K thanks to the enhanced frequency. This also applies to the single-threaded data and it’s clear that the faster Turbo clock is paying dividends. Interestingly, the stock i7-7700K is able to outperform a heavily overclocked i7-4770K which indicates the progress made over time. Setting the CPU to a mammoth 5.1GHz has a dramatic effect on the single-threaded performance which easily eclipses the rest of the field. On another note, the multi-threaded capabilities at 5,1GHz are greater than a stock 6-core i7-5820K.

Handbrake

The processor exhibits a small performance boost in video tasks when converting a 4K MP4 video file versus the previous generation offering. Furthermore, the FPS value isn’t too far behind the 6-core 5820K and I’d argue that the 4.5GHz boost helps to close the gap. The overclocked frequency is really beneficial during the conversion task and begins to rival higher core products with a lower base frequency.

WPrime

Rather surprisingly, the Intel i7-7700K reports a quicker pi calculation time than an overclocked i7-6700K during the 1024M benchmark. Saying that, the Skylake option fares better when working out the equation to fewer digits. Additionally, the i7-7700K running at 4.5GHz comprehensively beats an overclocked i7-4770K and isn’t too far away from the i7-5820K. After the overclock was applied, the 1024M calculation time dropped below 150 seconds and surpassed the i7-5820K. This is a great showing given the benchmark’s preference for processors with additional threads.

WinRAR

Here we can see the processor at stock values offers a very similar compression time to the previous flagship and struggles to contend with Intel’s 6-core alternative. As expected, the hefty overclock helps to narrow the gap, although it’s still some way off if you compare the different frequencies.

Memory Benchmarks – AIDA64

Memory Bandwidth

In terms of memory bandwidth, the Intel i7-7700K outputs slightly better write and copy results than the i7-6700K. On the other hand, the difference is minimal and can only be identified in synthetic applications.

Memory Latency

The processor’s memory bandwidth is superb and even manages to beat the i7-4770K which employs the DDR3 standard.

Discrete GPU Benchmarks

3DMark

During the 3DMark Fire Strike test, the i7-7770K attained an excellent score and almost pipped the i7-5960X. Once overclocked, the CPU performed better than an Intel i7-5820K running at 4.4GHz and was tantalising close to surpassing the i7-6950X.

Rise of the Tomb Raider

Switching from the i7-6700K to the i7-7700K in Rise of the Tomb raider causes the frame-rate to improve by a good amount Furthermore, the overclock ensures the CPU finishes in the top spot and complements the GTX 980Ti rather nicely.

Shadow of Mordor

Once again, the processor excels in gaming scenarios and remained ahead of the i7-6700K, although the gap is much smaller than the previous result. Overclocking the i7-7700K to 5.1GHz has a positive effect and allows the test bench to exceed a 140 frames-per-second average.

IGPU, IGPU + GPU Benchmarks

Unlike AMD’s APU range, none of the current Intel solutions can work alongside a discrete graphics card to enhance the graphics performance. In theory, it could become a viable option in DirectX 12 titles through parallel queues and cross-adapter support. Saying that, the integrated GPU segment’s weak performance and slow adoption rate of this feature make it a low priority for development studios. Of course, AMD’s Crossfire implementation isn’t widespread and revolves around outdated GPUs like the R7 250. Therefore, the importance of the iGPU working in tandem with a graphics card is exceedingly small.

3DMark

The Intel Graphics HD 630 struggles to post a 3D Mark Fire Strike score like all the other iGPUs on the market. However, the final result is better than the previous generation chip by a considerable amount. Clearly, the new graphics chipset provides a good performance boost but it’s nothing to write home about.

Dirt Rally

In Dirt Rally, the i7-7700K iGPU performs admirably and manages to uphold a stable frame-rate while using the low preset on a 1080p display. Once again, there’s a decent performance enhancement compared to the i7-6700K which allows the game to feel more fluid. Interestingly, the i7-7700K recorded a higher frame-rate before overclocking, but this is most likely down to a margin of error.

Tomb Raider

Tomb Raider on the lowest preset looks awful but it’s a necessity to obtain a playable frame-rate with an iGPU. As you can see, the i7-7700K maintains a pretty commendable lead over the i7-6700K although it’s not really a major leap in performance.

Overclocking

Overclocking

The Intel Core i7-7700K’s overclocking headroom depends on the cooling hardware at your disposal and silicon lottery.  Throughout the testing process, I analysed two processors and attempted to find a pattern which outlines the kind of overclocking results you can expect. Achieving 5.0GHz with a decent cooler isn’t overly challenging and it’s possible to reach this impressive figure with a voltage around 1.345v. Unfortunately, 5.1GHz is a much tougher task and requires a huge voltage increase. On average, 5.1GHz needed 1.435v and came perilously close to the 95C mark even with a top-tier closed-loop liquid cooling solution. Despite my best efforts, 5.2GHz just wasn’t a viable option and failed to post with 1.465-1.475v while running the fans at 100%. From my experience, the maximum potential is really 5.1GHz unless you’re using LN2. To put this into context, the highest overclock I managed on the i7-6700K was 4.8GHz.

Despite my best efforts, 5.2GHz just wasn’t a viable option and failed to post with 1.465-1.475v while running the fans at 100%. From my experience, the maximum potential is really 5.1GHz unless you’re using LN2. To put this into context, the highest overclock I managed on the i7-6700K was 4.8GHz. In addition to multipler overclocking, I endeavoured to enhance the overclocking result through BCLK adjustments. However, even the smallest tweak would result in instability alongside the 5.1GHz figure. Honestly, I’d recommend focusing on multiplier overclocking and ignore BCLK tweaking unless you want to eke out every last bit of performance.

Power Consumption and Temperatures

Power Consumption

During idle conditions, the i7-7700K consumes around 60-watts which demonstrate its efficient nature rather well. Overclocking the CPU doesn’t have a massive impact on the power draw and keeps the product within respectable levels. When you compare clock for clock, the i7-7700K uses less power than the i7-6700K. However, the results seem skewed by the contrasting frequencies. Under load, the i7-7700K hovers around the 165-watt mark which is a decent number given the 4.5GHz Turbo. Overclocking the CPU to 5.1GHz results in a power consumption around 182-watts which isn’t a huge increase over the i7-6700K running at 4.8GHz.

Temperatures

The i7-7700K’s thermal output is greater than its predecessor due to the higher Turbo frequency. Saying that, the temperatures only increase at a leisurely pace and remain under 70C. Please note, there doesn’t appear to be any kind of improvements to the thermal interface material which is a major disappointment. As previously mentioned, overclocking the CPU to 5.1GHz requires a hefty voltage increase and should only be attempted on high-end cooling hardware. Even then, I wouldn’t advise using such a large amount of voltage for 24/7 usage. While the CPU was stable at 5.1GHz, the temperatures are perilously close to the thermal limit.

Final Thoughts

Pricing

At the time of writing, the Intel Core i7-7700K hasn’t been released so it’s impossible to disclose a truly accurate retail price. Major stores might initially raise the processor’s cost to achieve greater profits during the initial rush. Rest assured, once the final prices are revealed, I’ll update the article accordingly. The sources so far suggest Intel could be releasing the i7-7700K at €434 which converts to £363.24 based on the current exchange rate. This would make the company’s new enthusiast flagship slightly more expensive than the i7-6700K’s launch price and pretty close to the i7-6800K. To clarify, the original listing which has since been removed could be a placeholder and shouldn’t be taken as completely accurate. Nevertheless, it looks likely Intel is adopting their standard pricing strategy and hasn’t entertained a price cut to discourage consumers from waiting for AMD’s new processor range.

Overview

The Intel Core i7-7700K builds upon the excellent framework from the i7-6700K and doesn’t really do anything significant to push the performance to higher levels, barring a basic frequency boost. Sadly, the CPU lacks IPC improvements, has the same thermal qualities and fails to make the case for upgrading unless you own a lower-end CPU from some time ago. Don’t get me wrong, the i7-7700K is a solid product and currently the best option on the market for high-end gamers. However, it seems like such an uninspired release which fails capture the enthusiast’s attention and prevent them from waiting for AMD Zen line-up.

Even though the performance gains are small, the i7-7770K excels in other areas such as video streaming and power consumption. If you compare identical frequencies, the i7-7700K consumes less power, although the difference is around 10-15W. I doubt this is going to make a huge difference to your electricity bills but it’s still a step forward nonetheless. On another note, Kaby Lake supports Intel’s ingenious Optane technology which has the potential to revolutionise storage speeds through non-volatile memory. Of course, companies need to create products based on Intel Optane and it might be a while until this becomes widely accessible. Saying that, it’s probably the highlight of Intel’s 7th generation processors and an invention which Intel deserve a lot of credit for. As mentioned earlier, the i7-7700K supports HDCP 2.2, Microsoft PlayReady 3.0 and can encode/decode VP9 as well as 4K 10-bit HEVC. This makes Kaby Lake a wonderful choice for those wanting to watch 4K Netflix streams. Personally, I think the video capabilities are going to appeal more to the laptop market and not a concern for desktop users.

In terms of overclocking headroom, the i7-7700K is able to reach 4.8-4.9GHz without a huge voltage increase. According to my testing on two separate samples, 4.8GHz was possible with minimal effort and a voltage of 1.323v-1.331v. Increasing the multiplier to x49 didn’t cause any stability after setting the voltage to 1.335v. Rather impressively, the magical 5.0GHz mark can be attained although you’ll probably need to be more ambitious with the voltage rating. The two samples I received needed 1.345v and 1.364v. Sadly, 5.1GHz is a huge task and should only be attempted if you have a good chip and exemplary cooling. This particular number isn’t stable without a massive voltage change and the lowest I could get to post was 1.435V. This appears the cut-off outside of LN2 because 5.2GHz resulted in constant crashing even when the voltage was set to 1.485V. For the average user, I’d recommend opting for 4.8GHz and fine-tuning the voltage for your CPU.

Throughout the review, I deliberated whether to dish out an award because the performance depends on an individual’s perspective. If you look at the new 14nm+ manufacturing process, it’s allowed for a higher turbo frequency, which leads to better performance. On the other hand, comparing the CPU with its predecessor at identical frequencies including 4.5GHz, 4.6GHz, 4.7GHz and 4.8GHz shows pretty much zero performance change. I eventually decided that the CPU doesn’t deserve an award because it shows a complete lack of ambition and continues stagnation in the CPU market. Despite the performance being better due to the higher clocks, it’s likely to cost more than Skylake and not worth bothering with if you own a Sandy Bridge, Haswell or Skylake processor. Hopefully, AMD releases something which can finally compete with Intel which instigates a pricing war and significant IPC gains over each generation. If you’re looking to build your first PC, or update an ageing system, the i7-7700K is a fine choice, beyond that, just stick with the current processor until more is known about Zen.

Pros

• Cross compatibility with Z170 motherboards
• Excellent overclocking headroom
• Good upgrade path for those still using older CPUs
• Great single-threaded performance
• Intel Optane technology has astounding potential
• HDCP 2.2 and Microsoft PlayReady 3.0 compliant
• Superb memory latency
• Supports VP9 decoding and 4K HEVC 10-bit decode/encode
• Tiny power improvement clock-for-clock versus Skylake

Cons

• AMD’s Zen architecture is just around the corner and looks promising
• Identical performance to the i7-6700K at the same frequencies
• Just a basic clock boost compared to Skylake
• Runs hotter and consumes more power than the i7-6700K

“The Intel Core i7-7700K is another solid offering and worthy of consideration if you’re using a relatively old processor. Unfortunately, it’s not a major upgrade from Skylake, has non-existent IPC gains and runs hotter due to the higher clock speeds. As AMD’s Zen approaches, the i7-7700K could be overshadowed by competing options although only time will tell.”

Intel Core i7-7700K Kaby Lake Processor Review