With four cores and 4.2 GHz maximum clock, the Core i5-7600K is the most high-end CPU of the new Core i5 seventh-generation series, codenamed Kaby Lake. Let’s test it!
Recently, Intel launched the seventh generation Core i processors, codenamed Kaby Lake. At first, were launched the Core i7 and Core i5 CPUs, and soon after, the Core i3, Pentium, and Celeron models. Those processors bring small changes compared to the sixth-generation ones: new video decoder for 4K video, improved Speed Shift technology (that dynamically adjusts the CPU clock,) and support to Optane technology (which is a future kind of high performance SSDs.)
The Core i5-7600K is the most high-end Core i5 CPU so far. It features 3.8 GHz base clock, 4.2 GHz turbo clock, 6 MiB of L3 cache, TDP of 91 W, and unlocked multiplier. It is manufactured under 14 nm process.
By now, the Core i5-7600K has no competitor from AMD (the Ryzen R5 CPUs will probably be these competitors, when launched,) so we tested it against a Core i5-6500 CPU, which is a slightly (15%) less expensive processor. So, keep in mind that they are not direct competitors.
Figure 1 unveils the Core i5-7600K CPU.

Figure 1: the Core i5-7600K CPU

Figure 2 shows the bottom of the CPU.

Figure 2: underside of the Core i5-7600K

In our benchmarks, we used the integrated video for the processing tests. However, for the gaming benchmarks, we disabled the integrated video and used a GeForce GTX 1080 video card on both CPUs, in order to see how the CPU power impact games, not the iGPU.
Let’s compare the main specs of the reviewed CPUs in the next page.
[nextpage title=”The Reviewed CPUs”]
In the tables below, we compare the main features of the CPUs included in our review.

CPU	Cores	HT	IGP	Internal Clock	Turbo Clock	Core	Tech.	TDP	Socket	Price
Core i5-7600K	4	No	No	3.8 GHz	4.2 GHz	Kaby Lake	14 nm	91 W	LGA1151	USD 240
Core i5-6500	4	No	No	3.2 GHz	3.6 GHz	Skylake	14 nm	65 W	LGA1151	USD 205

Below you can see the memory configuration for each CPU.

CPU	L2 Cache	L3 Cache	Memory Support	Memory Channels
Core i5-7600K	4 x 256 kiB	6 MiB	Up to DDR4-2133 or DDR3L-1600	2
Core i5-6500	4 x 256 kiB	6 MiB	Up to DDR4-2133 or DDR3L-1600	2

[nextpage title=”How We Tested”]During our benchmarking sessions, we used the configuration listed below. Between our benchmarking sessions, the only variable devicand was the CPU being tested, besides the motherboard and memory, which had to be replaced to match the different CPUs.
Hardware Configuration

• Motherboard: Gigabyte AORUS Z270X-Gaming 7
• Memory: 16 GiB DDR4-2133, two G.Skill Ripjaws V F4-2133C15D-16GVR 8 GiB memory modules configured at 2133 MHz
• Boot drive: WD Blue 1,000 GiB SSD
• Video Card: GeForce GTX 1080 (on games), integrated video on the other tests
• Video Monitor: Philips 236VL
• Power Supply: Corsair VS500

Operating System Configuration

• Windows 10 Home 64-bit
• NTFS
• Video resolution: 1920 x 1080 60 Hz

Driver Versions

• NVIDIA driver version: 378.49

Software Used

• 3DMark 1.5.915
• Cinebench R15
• CPU-Z 1.78
• DivX 10.6
• Media Espresso 6.7
• PCMark 8
• Photoshop CC
• WinRAR 4.2
• Dirt Rally
• GTA V
• Hitman
• Mad Max
• Rise of the Tomb Rider

Error Margin
We adopted a 4% error margin. Thus, differences below 4% cannot be considered relevant. In other words, products with a performance difference below 4% should be considered as having similar performance.
[nextpage title=”PCMark 8″]
PCMark 8 is a benchmarking software that uses real-world applications to measure the computer performance. We ran three tests: Home, which includes web browsing, writing, light gaming, photo editing, and video chat tests; Creative, that includes web surfing, video editing, group video chat, video conversion, and gaming; and Work, which runs tasks such as writing documents, web browsing, spreadsheets, editing, and video chatting. Let’s see the results.

On the PCMark 8 Home benchmark, the Core i5-7600K was 11% faster than the Core i5-6500.

On the Creative benchmark, the Core i5-7600K was 14% faster than the Core i5-6500.

On the Work benchmark, the Core i5-7600K was 11% faster than the Core i5-6500.
[nextpage title=”3DMark”]

3DMark is a program with a set of several 3D benchmarks. Fire Strike runs a “heavy” DirectX 11 simulation. Sky Diver also measures DirectX 11 performance, and is aimed on average computers. The Cloud Gate benchmark measures DirectX 10 performance, and the Ice Storm Extreme measures DirectX 9 performance and is targeted to entry-level computers, so we don’t ran it.

On Fire Strike, the Core i5-7600K was 13% faster than the Core i5-6500.

On the Sky Diver benchmark, the Core i5-7600K was 15% faster than the Core i5-6500.

On the Cloud Gate benchmark, the Core i5-7600K was 15% faster than the Core i5-6500.

[nextpage title=”Performance in programs”]

 Cinebench R15

Cinebench R15 is based on the Cinema 4D software. It is very useful to measure the performance gain obtained by the presence of several processing cores while rendering heavy 3D images. Rendering is an area where a bigger number of cores helps a lot, because usually this kind of software recognize several processors (Cinebench R15, for example, can use up to 256 processing cores).
We ran the CPU benchmark, which renders a complex image using all the processing cores (real and virtual) to speed up the process. The result is given as a score.

On Cinebench R15 CPU benchmark, the Core i5-7600K was 16% faster than the Core i5-6500.

CPU-Z

On its current version, the well-known hardware identification software CPU-Z comes with a benchmarking tool, which measures CPU performance for one core and for all available cores.

On the single thread benchmark, the Core i5-7600K was 27% faster than the Core i5-6500.

On the multiple thread benchmark, the Core i5-7600K was 29% faster than the Core i5-6500.

DivX

We used the DivX converter, a tool included in the DivX package, in order to measure the encoding performance using this codec. The DivX codec is capable of recognizing and using all available cores and the SSE4 instruction set.
We converted a Full HD, six-minute long .mov video file into an .avi file, using the “HD 1080p” output profile. The results below are given in seconds, so the lower the better.

On DivX encoding, the Core i5-7600K was 23% faster than the Core i5-6500.

Media Espresso

Media Espresso is a video conversion program that uses the graphics processing unit of the video engine to speed up the conversion process. We converted a 1 GiB, 1920x1080i, 23,738 kbps, .mov video file to a smaller 320×200, H.264, .MP4 file for viewing on a smartphone. The results below are given in seconds, so the lower the better.

Here the Core i5-7600K was 15% faster than the Core i5-6500.

Photoshop CC

The best way to measure the performance of a CPU is by using real programs. The problem, of course, is to create a methodology that offers precise results. For Photoshop CC, we used a script named “Retouch Artist Speed Test,” which applies a series of filters to a standard image and gives the time Photoshop takes to run all of them. The results are given in seconds, so the less, the best.

In this test, the Core i5-7600K was 22% faster than the Core i5-6500.

WinRAR

Another task where the CPU is very demanded is on file compacting. We ran a test compacting a folder with 8 GiB on 6.813 files to a file, using WinRAR 4.2. The graph below shows the time taken on each test.

On WinRAR, the Core i5-7600K was 11% faster than the Core i5-6500.
[nextpage title=”Gaming Performance”]

 Dirt Rally

Dirt Rally is an off-road racing game released in April 2015, using Ego engine. To measure performance using this game, we ran the performance test included in the game, in 1920 x 1080 (Full HD) resolution and image quality configured as “medium” and MSAA off.
The results below are expressed in frames per second (fps).

In this game, the Core i5-7600K was 18% faster than the Core i5-6500.

Grand Theft Auto V

Grand Theft Auto V, or simply GTA V, is an open-world action game released for PCs in April of 2015, using the RAGE engine. In order to measure the performance on this game, we ran the performance test of the game, measuring the framerate with FRAPS. We ran GTA V at Full HD, with all image quality set as “high” and MSAA off.

The results below are expressed in frames per second.

On GTA V, both CPUs performed similarly.

Hitman

Hitman is an action/stealth game, launched in March 2016, that uses a DirectX 12 compatible version of the Glacier 2 engine. To measure performance in this game, we ran the benchmark in it, measuring the framerate with FRAPS. We ran this game with DirectX 12 enabled, with image quality set as “high”.
The results below, in Full HD and 4K, are expressed in frames per second.

On Hitman, the Core i5-7600K was 12% faster than the Core i5-6500.

Mad Max

Mad Max is an open-world action game launched in September of 2015, using the Avalanche engine. In order to measure the performance using this game, we ran its intro, measuring the framerate with FRAPS three times. We ran the game with image quality set as “high”.

The results below are expressed in fps and they are the mean between the three collected results.

On Mad Max, the Core i5-7600K performed similarly to the Core i5-6500.

Rise of the Tomb Rider

Rise of the Tomb Rider is an adventure/action game launched in January of 2016, based on Foundation engine. In order to measure the performance using this game, we ran the benchmark included on it, using Full HD resolution and graphics quality set to “medium”.
The results below are expressed in frames per second.

Also on Rise of the Tomb Rider, the performance was also the same on both CPUs.
[nextpage title=”Overclocking”]
As you may tell because of the “K” at the end of the CPU’s name, the Core i5-7600K has an unlocked multiplier, which means you can overclocking it just by modifying its clock multiplier.
We were able to configure the CPU to run stable at 4.8 GHz (100 MHz reference clock and x48 multiplier), with the original voltages. It may be possible to reach higher frequencies if you “play” with the available adjusts.
However, if you intend overclocking the Core i5-7600K, it is good to use a high-end cooler: using a simple Intel stock cooler while overclocking, the CPU easily reached 85 °C and, at this temperature, reduced the clock automatically. When we used a high-end cooler, the CPU mantained the desired clock all the time.
It is also good to keep in mind that the overclock capability depends on pure luck, since two CPUs of same model can reach different maximum clocks.
[nextpage title=”Conclusions”]The new Core i5-7600K obtained an expressive advantage over the Core i5-6500 on all CPU benchmarks. Add to this the fact it is unlocked and offer a great potential for overclocking, it is a great option for the user who is looking for a CPU with great cost/benefit ratio, and even more if you are an adept of overclocking.
On the other hand, if you are building a gaming PC, the performance gain by using this model can be small. If you have a limited budget, it may be better to buy a less expensive CPU (like the Core i5-6500 or its sucessor, the Core i5-6500, or even a Core i3 CPU) and use the saved money to invest on a stronger video card.