Intel Core i5 6600K Review | 78 Data compared

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  • Avg. price: ~£250
  • PassMark benchmark result: 6301
  • N. of physical cores: 4
  • CPU boost clock speed: 3.9 GHz

Intel Core i5 6600K review. Compare 78 technical specifications and user reviews to see how it ranks among processors and if it is worth buying.

4.5

Overall score

What it is: An overall evaluation of the processor's quality, based on technical analyses and user reviews.

When it matters: When you need a quick reference to identify the best processors on the market.

Score components:

90.0%

3.9

Technical Score

10.0%

9.5

User score

Poor
3.9

Technical Score

What it is: An assessment of the processor's technical performance, covering key areas such as processing performance, core configuration, efficiency, platform support, integrated features, and thermal behavior.

When it matters: When you want to compare processors based on technical performance and available features.

Score components:

60.0%

3.2

Performance

18.0%

4.5

Cache & Architecture

10.0%

5.1

Memory & PCIe

7.0%

3.9

Power & Thermal

4.0%

7.6

Platform

1.0%

6.8

Integrated Graphics

Poor
9.5

User score

What it is: A rating that combines user reviews and the total number of reviews received by the processor.

When it matters: When you want to know how a processor performs in real workloads and how reliable it is for gaming, productivity, and efficiency according to user feedback.

Score components:

70.0%

9.3

User reviews

30.0%

10

Popularity

User score:
United Kingdom
amazon
4.7
(1219)
amazon
4.6
(911)
amazon
4.6
(12)
amazon
3.3
(3)

(Reviews last updated: May 2026)

Exceptional
  • 3.4
    Gaming

    Score components:

    30.0%

    3.7

    PassMark single-core benchmark score

    25.0%

    4.0

    Geekbench 6 single-core benchmark score

    20.0%

    4.3

    CPU boost clock speed

    17.0%

    1.8

    L3 cache

    8.0%

    1.8

    N. of physical cores

  • 2.0
    Video editing

    Score components:

    45.0%

    2.4

    Geekbench 6 multi-core benchmark score

    20.0%

    1.8

    N. of physical cores

    20.0%

    1.6

    CPU threads

    15.0%

    1.8

    L3 cache

  • intel-core-i5-6600k
intel-core-i5-6600k

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Available: ranking among products currently available (including other versions of this product).
All: ranking among all products in the database.

Verdict

The Intel Core i5-6600K is a 6th Generation 'Skylake' quad-core desktop processor featuring 4 cores, 4 threads, a 3.5 GHz base frequency, and a 3.9 GHz max turbo frequency. Built on a 14nm process with a 91W TDP, it includes 6MB of Intel Smart Cache, supports DDR4-2133 and DDR3L-1600 memory, and uses the LGA 1151 socket. Main pros include its unlocked multiplier for easy overclocking, strong single-core performance for its era, and integrated Intel HD Graphics 530 with 4K support. Notable cons are the lack of Hyper-Threading, a higher TDP compared to non-K variants, and it is increasingly limited in modern multi-threaded applications and games due to its 4-thread count.

Technical Specifications of processor Intel Core i5 6600K

Technical Score

What it is: An assessment of the processor's technical performance, covering key areas such as processing performance, core configuration, efficiency, platform support, integrated features, and thermal behavior.

When it matters: When you want to compare processors based on technical performance and available features.

Score components:

60.0%

3.2

Performance

18.0%

4.5

Cache & Architecture

10.0%

5.1

Memory & PCIe

7.0%

3.9

Power & Thermal

4.0%

7.6

Platform

1.0%

6.8

Integrated Graphics

3.9
Intel Core i5 6600K has a technical score of 3.89 points, which is lower than that of 85.4% of products in this category.
User score

What it is: A rating that combines user reviews and the total number of reviews received by the processor.

When it matters: When you want to know how a processor performs in real workloads and how reliable it is for gaming, productivity, and efficiency according to user feedback.

Score components:

70.0%

9.3

User reviews

30.0%

10

Popularity

User score:
United Kingdom
amazon
4.7
(1219)
amazon
4.6
(911)
amazon
4.6
(12)
amazon
3.3
(3)

(Reviews last updated: May 2026)

9.5
Intel Core i5 6600K has a user score of 9.52 points, which is higher than that of 94.5% of products in this category.
Popularity
What it is: An indicator based on the number of reviews received by the processor.
When it matters: When you prefer to choose a processor reviewed and selected by many other buyers.
10
Intel Core i5 6600K has a popularity of 10 points, which is higher than 88.3% of products in this category.
Ratio quality/price

What it is: An indicator that combines the processor's overall rating with its cost.

When it matters: When you are looking for a processor with a good balance between performance, efficiency, and price.

Score components:

60.0%

4.5

Overall score

40.0%

9.2

Price

5.9
Intel Core i5 6600K has a quality-to-price ratio of 5.9 points, which is lower than 69.8% of products in this category.
Brand name
What it is: The manufacturer or brand of the product.
When it matters: When you prefer a specific ecosystem, support network, or design philosophy.

Importance: MEDIUM

Intel
Processor type
What it is: The kind of system the processor is built for, such as desktop PCs, laptops, workstations, or servers.
When it matters: When you want a processor meant for the kind of machine you are actually building or buying, rather than a chip aimed at a different class of system.

Importance: HIGH

desktop
Intel Core i5 6600K belongs to the desktop processor class, which is more advanced than that of 56% of processors and equal to that of 37.9% of processors.
CPU socket
What it is: The physical socket the processor fits into on the motherboard.
When it matters: When you need to make sure the CPU can actually be installed on a specific motherboard.

Importance: HIGH

LGA1151
Intel Core i5 6600K uses the LGA1151 CPU socket, which is newer than that of 60.1% of processors and equal to that of 9.7% of processors.
Chipset
What it is: The motherboard chipset families officially meant to work with the processor.
When it matters: When you are checking whether a CPU will work with the motherboard features and platform you plan to use.

Importance: HIGH

Intel 100 Series, Intel 200 Series
Intel Core i5 6600K supports Intel 100 Series, Intel 200 Series chipsets, which is broader compatibility than 50% of processors and equal to that of 2.1% of processors.
CPU architecture
What it is: The processor family or design generation behind the chip, such as Zen 4 or Raptor Lake.
When it matters: When you are comparing CPUs across generations and want a clearer sense of their design age, feature level, and expected performance class.

Importance: HIGH

x86-64
Intel Core i5 6600K uses the x86-64 architecture, which is more advanced than that of 1.7% of processors and equal to that of 98.3% of processors.
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N. of physical cores
What it is: The number of physical CPU cores on the processor.
When it matters: When you run workloads that benefit from more real cores.

Importance: HIGH

Good value: 8+

4
Intel Core i5 6600K has 4 CPU cores, which is fewer than 50.7% of processors and equal to 28.5% of processors.
CPU threads
What it is: The total number of processing threads the CPU can handle at once.
When it matters: When you run heavily threaded workloads or multitask a lot.

Importance: HIGH

Good value: 16+

4
Intel Core i5 6600K offers 4 CPU threads, which is fewer than 67.3% of processors and equal to 26.6% of processors.
Threads per core
What it is: The number of threads each physical core can handle at once.
When it matters: When you want to understand how much thread-level parallelism each core can provide in multitasking or heavily threaded work.

Importance: MEDIUM

Good value: 2

1
Intel Core i5 6600K offers 1 threads per core, which is fewer than 69.7% of processors and equal to 30.3% of processors.
CPU boost clock speed
What it is: The highest clock speed the processor can reach under boost conditions.
When it matters: When you care about peak speed in short bursts.

Importance: HIGH

Good value: >4.7 GHz

3.9 GHz
Intel Core i5 6600K reaches a boost clock of 3.9 GHz which is lower than that of 65% of processors and equal to that of 3.5% of processors.
CPU base clock speed
What it is: The processor's normal all-core starting frequency before boost behavior raises clocks temporarily.
When it matters: When you care about steadier performance in longer workloads rather than short burst speed alone.

Importance: MEDIUM

4 x 3.5 GHz
Intel Core i5 6600K has a base clock of 4x3.5 GHz which is equal to that of 100% of processors.
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Semiconductor size
What it is: The manufacturing process node used to produce the processor, usually expressed in nanometers.
When it matters: When efficiency, heat, and the relative modernity of the chip-making process matter to your comparison.

Importance: HIGH

Good value: <10 nm

14 nm
Intel Core i5 6600K uses a 14 nm process node, which is older than that of 50.8% of processors and equal to that of 33.7% of processors.
Foundry
What it is: The semiconductor manufacturer that physically fabricates the processor chip.
When it matters: When process source, manufacturing generation, or foundry differences matter to your comparison more than day-to-day performance alone.

Importance: MEDIUM

Intel 14 nm
Intel Core i5 6600K is built on the Intel 14 nm foundry process, which is less advanced than that of 55.2% of processors and equal to that of 29.3% of processors.
L3 cache
What it is: The total amount of L3 cache available on the processor.
When it matters: When you want better performance in cache-sensitive workloads and games.

Importance: MEDIUM

Good value: >=16 MB

6 MB
Intel Core i5 6600K has an L3 cache of 6 MB which is smaller than that of 60.4% of processors and equal to that of 9.7% of processors.
L2 cache
What it is: The total amount of L2 cache available across the processor.
When it matters: When you want to compare CPU design efficiency and how much fast intermediate cache the cores have available.

Importance: MEDIUM

Good value: >=6 MB

1 MB
Intel Core i5 6600K has an L2 cache of 1 MB which is smaller than that of 67.1% of processors and equal to that of 17.6% of processors.
L1 cache
What it is: The total amount of L1 cache built into the processor, which sits closest to the cores.
When it matters: When you are comparing low-level CPU design details rather than the broader performance picture buyers usually notice first.

Importance: MEDIUM

Good value: >=512 KB

256 KB
Intel Core i5 6600K has an L1 cache of 256 KB which is smaller than that of 59.4% of processors and equal to that of 18.5% of processors.
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DDR memory version
What it is: The RAM generation the processor is designed to support, such as DDR4 or DDR5.
When it matters: When you need the CPU to match the kind of memory platform you want to buy or reuse.

Importance: MEDIUM

Good value: DDR5

DDR3L/DDR4
Intel Core i5 6600K supports DDR DDR3L/DDR4, which is older than that of 77.7% of processors and equal to that of 5.4% of processors.
Maximum memory speed
What it is: The highest official memory speed supported by the processor.
When it matters: When you choose RAM and want to know the supported speed ceiling.

Importance: HIGH

Good value: >=4800 MHz

2,133 MHz
Intel Core i5 6600K supports memory speeds up to 2133 MHz, which is lower than that of 75.6% of processors and equal to 8.8% of processors.
Max memory speed (JEDEC)
What it is: The highest official RAM speed the processor supports under standard JEDEC settings, before any memory overclocking profiles are applied.
When it matters: When officially supported stock RAM speed matters more than XMP, EXPO, or manual memory tuning.

Importance: MEDIUM

Good value: >=5600 MHz

2,133 MHz
Intel Core i5 6600K supports JEDEC memory speeds up to 2133 MHz, which is lower than that of 83.8% of processors and equal to 1.6% of processors.
Max memory speed (XMP / EXPO)
What it is: The highest memory speed supported through XMP or EXPO profiles.
When it matters: When you want faster RAM through memory profiles.

Importance: MEDIUM

Good value: >=5200 MHz

?
Maximum memory capacity
What it is: The largest total amount of memory officially supported by the processor.
When it matters: When you plan a system with very large RAM capacity.

Importance: HIGH

Good value: >=128 GB

64 GB
Intel Core i5 6600K supports up to 64 GB of memory, which is more than 28.4% of processors and equal to 27.6% of processors.
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Integrated graphics
What it is: Includes built-in graphics, so the system can output video without a separate graphics card.
When it matters: When you want the PC to work without a dedicated GPU, or you are building an office, media, compact, or troubleshooting-friendly system.

Importance: HIGH

yes
Intel Core i5 6600K includes integrated graphics. 87.6% of processors include integrated graphics.
Integrated GPU model
What it is: The model name of the integrated graphics processor, if present.
When it matters: When you plan to use the CPU's built-in graphics.

Importance: MEDIUM

Intel HD Graphics 530
Intel Core i5 6600K uses the Intel HD Graphics 530 integrated GPU, which is less advanced than that in 78.4% of processors and equal to that in 2.3% of processors.
Integrated GPU execution units
What it is: The number of execution units available in the integrated graphics part of the processor.
When it matters: When you plan to rely on built-in graphics and want a better sense of its light gaming, display, or media capability.

Importance: MEDIUM

Good value: >=24

24
Intel Core i5 6600K has 24 GPU execution units, which is more than 49.2% of processors and equal to 21.6% of processors.
Integrated GPU base frequency
What it is: The base operating frequency of the integrated GPU.
When it matters: When integrated graphics performance matters to you.

Importance: MEDIUM

Good value: >=350 MHz

350 MHz
Intel Core i5 6600K has an integrated GPU clock of 350 MHz which is higher than that of 43.5% of processors and equal to that of 29.6% of processors.
Integrated media encoders/decoders
What it is: The hardware media formats the processor can encode or decode directly.
When it matters: When you stream, edit video, or rely on hardware media acceleration.

Importance: LOW

H.264 (HW decode/encode), H.265 (HW decode/encode), VP9 (HW decode), VP8 (HW decode/encode), MPEG-2 (HW decode/encode), VC-1
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TDP (Thermal design power)
What it is: The rated thermal design power, which gives a general idea of cooling and power needs.
When it matters: When you choose a cooler or build in a tighter case.

Importance: HIGH

Good value: <30 W

91 W
Intel Core i5 6600K has a TDP of 91 W which is higher than that of 88.2% of processors and equal to that of 0.5% of processors.
Base power (PL1)
What it is: The sustained power target used for longer CPU loads.
When it matters: When you choose cooling and power delivery for sustained workloads.

Importance: MEDIUM

Good value: <30 W

91 W
Intel Core i5 6600K has a base power of 91 W which is higher than that of 88.4% of processors and equal to that of 0.5% of processors.
Boost power (PL2)
What it is: The short-term boost power limit the processor may draw under heavier turbo loads.
When it matters: When you size cooling and power delivery for peak turbo behavior.

Importance: MEDIUM

Good value: <50 W

91 W
Intel Core i5 6600K has a boost power of 91 W which is higher than that of 66.4% of processors and equal to that of 0.5% of processors.
Tau (power duration limit)
What it is: The time limit the CPU can stay at higher boost power before dropping toward sustained power.
When it matters: When you want to understand turbo behavior under longer loads.

Importance: MEDIUM

Good value: <=28 s

8 seconds
Intel Core i5 6600K has a turbo duration of 8 seconds which is longer than that of 89.1% of processors and equal to that of 7.1% of processors.
Configurable TDP
What it is: Allows the processor to run in alternate power modes instead of being fixed to one default TDP target.
When it matters: When you want more control over heat, noise, and power draw in compact systems, quieter builds, or thermally limited machines.

Importance: LOW

no
Intel Core i5 6600K does not support configurable TDP. 52.9% of processors support configurable TDP.
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Intel Core i5 6600K vs the average processor

  • Unlocked for overclocking
    Intel Core i5 6600K has an unlocked multiplier, the average processor does not.
    What it is: Has an unlocked CPU multiplier, which makes manual CPU overclocking much easier on supported platforms.
    When it matters: When you plan to push clock speeds beyond stock settings instead of leaving the processor completely at default behavior.

    Importance: MEDIUM

    Intel Core i5 6600K has an unlocked multiplier, the average processor does not.
  • Supports memory overclocking
    Intel Core i5 6600K supports memory overclocking, the average processor does not.
    What it is: Allows memory speeds beyond official stock settings through manual tuning or profile-based overclocking.
    When it matters: When you want to push RAM performance higher than stock support allows, especially in enthusiast or gaming builds.

    Importance: MEDIUM

    Intel Core i5 6600K supports memory overclocking, the average processor does not.
  • 10x more popular
    Intel Core i5 6600K is more popular than the average processor (10.00 vs 1.000).
    What it is: An indicator based on the number of reviews received by the processor.
    When it matters: When you prefer to choose a processor reviewed and selected by many other buyers.
    Intel Core i5 6600K is more popular than the average processor (10.00 vs 1.000).10 vs 1
  • 19% higher user score
    Intel Core i5 6600K has a higher user score than the average processor (9.52 vs 8.000).
    What it is: A rating that combines user reviews and the total number of reviews received by the processor.
    When it matters: When you want to know how a processor performs in real workloads and how reliable it is for gaming, productivity, and efficiency according to user feedback.
    Intel Core i5 6600K has a higher user score than the average processor (9.52 vs 8.000).9.52 vs 8
  • Modern CPU socket
    Intel Core i5 6600K uses a more modern CPU socket than the average processor (LGA1,151 vs FP2).
    What it is: The physical socket the processor fits into on the motherboard.
    When it matters: When you need to make sure the CPU can actually be installed on a specific motherboard.

    Importance: HIGH

    Intel Core i5 6600K uses a more modern CPU socket than the average processor (LGA1,151 vs FP2).LGA1151 vs FP2
  • Modern CPU socket
    Intel Core i5 6600K uses a more modern CPU socket than the average processor (LGA1,151 vs FP2).
  • Unlocked for overclocking
    Intel Core i5 6600K has an unlocked multiplier, the average processor does not.
  • Supports memory overclocking
    Intel Core i5 6600K supports memory overclocking, the average processor does not.
  • 5 year/s older release date
    Intel Core i5 6600K has an older release date than the average processor (2,015 vs 2,020).
    August 2015
  • No crypto acceleration
    Intel Core i5 6600K does not include crypto acceleration, the average processor does.
  • Narrower instruction support
    Intel Core i5 6600K supports a narrower instruction set than the average processor (MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, AVX, AVX2, FMA3, AES, BMI1, BMI2 vs MMX, SSE, SSE2, SSE3, SSSE3, SSE4A, SSE4.1, SSE4.2, AVX, AVX2, F16C, FMA3, AES, SHA).
  • 48.5% weaker multi-core performance
    Intel Core i5 6600K has a lower multi-core performance than the average processor (1,433 vs 2,783). The average processor scores 2,783 in Cinebench R20 multi-core.
  • 2 fewer CPU cores
    Intel Core i5 6600K has fewer CPU cores than the average processor (4 vs 6). The average processor has 6 CPU cores.
  • No multithreading support
    Intel Core i5 6600K does not support multithreading, the average processor does.
  • 9.3% lower boost clock
    Intel Core i5 6600K has a lower boost clock speed than the average processor (3.9 GHz vs 4.3 GHz). The average processor reaches boost clock speed of 4.3 GHz.
  • 16.7% lower Cinebench R20 single-core score
    Intel Core i5 6600K has a lower Cinebench R20 single-core score than the average processor (403 vs 484). The average processor scores 484 in Cinebench R20 single-core.
  • 4 fewer CPU threads
    Intel Core i5 6600K has fewer CPU threads than the average processor (4 vs 8). The average processor has 8 CPU threads.
  • 40.2% lower PassMark score
    Intel Core i5 6600K has a lower PassMark benchmark score than the average processor (6,301 vs 10,532.5). The average processor scores 10,532.5 in PassMark benchmark.
  • 1 fewer threads per core
    Intel Core i5 6600K has fewer threads per core than the average processor (1 vs 2). The average processor offers 2 threads per core.
  • 6.8% weaker single-core performance
    Intel Core i5 6600K has a lower PassMark single-core score than the average processor (2,314 vs 2,483). The average processor scores 2,483 in PassMark single-core.
  • 15.9% lower multi-core score
    Intel Core i5 6600K has a lower Geekbench 6 multi-core score than the average processor (4,033 vs 4,793). The average processor scores 4,793 in Geekbench 6 multi-core.
  • 16.7% larger process node
    Intel Core i5 6600K has a higher process node than the average processor (14 nm vs 12 nm). The average processor uses a process node of 12 nm.
  • 60% smaller L2 cache
    Intel Core i5 6600K has a lower L2 cache than the average processor (1 MB vs 2.5 MB). The average processor has L2 cache of 2.5 MB.
  • 50% less L2 per core
    Intel Core i5 6600K has less L2 cache per core than the average processor (0.3 MB/core vs 0.5 MB/core). The average processor provides 0.5 MB/core of L2 cache per core.
  • 12.5% less L3 per core
    Intel Core i5 6600K has less L3 cache per core than the average processor (1.5 MB/core vs 1.714 MB/core). The average processor provides 1.714 MB/core of L3 cache per core.
  • 33.3% smaller L1 cache
    Intel Core i5 6600K has a lower L1 cache than the average processor (256 KB vs 384 KB). The average processor has L1 cache of 384 KB.
  • 64.6% fewer transistors
    Intel Core i5 6600K has fewer transistors than the average processor (1.8 billion vs 4.95 billion). The average processor has 4.95 billion transistors.
  • 25% smaller L3 cache
    Intel Core i5 6600K has a lower L3 cache than the average processor (6 MB vs 8 MB). The average processor has L3 cache of 8 MB.
  • Less advanced microarchitecture
    Intel Core i5 6600K uses a less advanced microarchitecture than the average processor (Skylake vs Kaby Lake).
  • 25.5% lower memory bandwidth
    Intel Core i5 6600K has a lower memory bandwidth than the average processor (34.1 GB/s vs 45.8 GB/s). The average processor offers memory bandwidth of 45.8 GB/s.
  • 27.3% lower memory speed
    Intel Core i5 6600K has a lower maximum memory speed than the average processor (2,133 MHz vs 2,933 MHz). The average processor supports memory speed of 2,933 MHz.
  • Older DDR support
    Intel Core i5 6600K supports an older DDR generation than the average processor (DDR3L/DDR4 vs DDR4).
  • Inferior integrated GPU
    Intel Core i5 6600K uses an inferior integrated GPU to the average processor (Intel HD Graphics 530 vs Intel UHD Graphics 630).
  • 2.02x higher base power
    Intel Core i5 6600K has a higher base power draw than the average processor (91 W vs 45 W). The average processor has a base power draw of 45 W.
  • No configurable TDP
    Intel Core i5 6600K does not support configurable TDP, the average processor does.
  • 2.02x higher TDP
    Intel Core i5 6600K has a higher TDP than the average processor (91 W vs 45 W). The average processor has a TDP of 45 W.
  • 42.2% higher boost power
    Intel Core i5 6600K has a higher boost power draw than the average processor (91 W vs 64 W). The average processor has a boost power draw of 64 W.
  • 20 seconds shorter turbo duration
    Intel Core i5 6600K has a lower turbo duration limit than the average processor (8 seconds vs 28 seconds). The average processor maintains turbo for 28 seconds.
  • 48.5% weaker multi-core performance
    Intel Core i5 6600K has a lower multi-core performance than the average processor (1,433 vs 2,783). The average processor scores 2,783 in Cinebench R20 multi-core.
    What it is: A Cinebench R20 score that reflects how well the processor handles long, heavy rendering workloads across many cores.
    When it matters: When you care about sustained multi-core performance in rendering, compiling, heavy creation work, or productivity workloads that use many threads.

    Importance: HIGH

    Good value: >4700

    Intel Core i5 6600K has a lower multi-core performance than the average processor (1,433 vs 2,783). The average processor scores 2,783 in Cinebench R20 multi-core.1,433 vs 2,783
  • 2 fewer CPU cores
    Intel Core i5 6600K has fewer CPU cores than the average processor (4 vs 6). The average processor has 6 CPU cores.
    What it is: The number of physical CPU cores on the processor.
    When it matters: When you run workloads that benefit from more real cores.

    Importance: HIGH

    Good value: 8+

    Intel Core i5 6600K has fewer CPU cores than the average processor (4 vs 6). The average processor has 6 CPU cores.4 vs 6
  • No multithreading support
    Intel Core i5 6600K does not support multithreading, the average processor does.
    What it is: Lets each physical core run more than one thread at the same time, such as with Hyper-Threading or SMT.
    When it matters: When multitasking, rendering, compiling, virtualization, or other thread-heavy work benefits from more total processing threads.

    Importance: HIGH

    Intel Core i5 6600K does not support multithreading, the average processor does.
  • 2.02x higher base power
    Intel Core i5 6600K has a higher base power draw than the average processor (91 W vs 45 W). The average processor has a base power draw of 45 W.
    What it is: The sustained power target used for longer CPU loads.
    When it matters: When you choose cooling and power delivery for sustained workloads.

    Importance: MEDIUM

    Good value: <30 W

    Intel Core i5 6600K has a higher base power draw than the average processor (91 W vs 45 W). The average processor has a base power draw of 45 W.91 W vs 45 W
  • 9.3% lower boost clock
    Intel Core i5 6600K has a lower boost clock speed than the average processor (3.9 GHz vs 4.3 GHz). The average processor reaches boost clock speed of 4.3 GHz.
    What it is: The highest clock speed the processor can reach under boost conditions.
    When it matters: When you care about peak speed in short bursts.

    Importance: HIGH

    Good value: >4.7 GHz

    Intel Core i5 6600K has a lower boost clock speed than the average processor (3.9 GHz vs 4.3 GHz). The average processor reaches boost clock speed of 4.3 GHz.3.9 GHz vs 4.3 GHz
  • 16.7% lower Cinebench R20 single-core score
    Intel Core i5 6600K has a lower Cinebench R20 single-core score than the average processor (403 vs 484). The average processor scores 484 in Cinebench R20 single-core.
    What it is: A Cinebench R20 benchmark score that reflects single-core CPU performance.
    When it matters: When you care about lighter workloads, interface responsiveness, or software that still depends heavily on one fast core.

    Importance: HIGH

    Good value: >600

    Intel Core i5 6600K has a lower Cinebench R20 single-core score than the average processor (403 vs 484). The average processor scores 484 in Cinebench R20 single-core.403 vs 484
  • 16.7% larger process node
    Intel Core i5 6600K has a higher process node than the average processor (14 nm vs 12 nm). The average processor uses a process node of 12 nm.
    What it is: The manufacturing process node used to produce the processor, usually expressed in nanometers.
    When it matters: When efficiency, heat, and the relative modernity of the chip-making process matter to your comparison.

    Importance: HIGH

    Good value: <10 nm

    Intel Core i5 6600K has a higher process node than the average processor (14 nm vs 12 nm). The average processor uses a process node of 12 nm.14 nm vs 12 nm
  • 4 fewer CPU threads
    Intel Core i5 6600K has fewer CPU threads than the average processor (4 vs 8). The average processor has 8 CPU threads.
    What it is: The total number of processing threads the CPU can handle at once.
    When it matters: When you run heavily threaded workloads or multitask a lot.

    Importance: HIGH

    Good value: 16+

    Intel Core i5 6600K has fewer CPU threads than the average processor (4 vs 8). The average processor has 8 CPU threads.4 vs 8

Graphic comparison of Intel Core i5 6600K and other processors

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Third-party reviews

(Reviews last updated: May 2026)

What customers like about Intel Core i5 6600K?

  • Excellent overclocking potential with a free multiplier
  • Strong single-core performance ideal for gaming
  • Support for modern features like DDR4 RAM and NVMe storage via the Z170 chipset
  • Highly efficient power consumption compared to previous generations
  • Runs relatively cool, often reaching high clocks with standard air cooling
  • Significant improvement in integrated graphics performance over the Haswell series

What customers dislike about Intel Core i5 6600K?

  • Lacks Hyper-Threading, limiting it to only 4 threads
  • Frequent 'stuttering' in modern CPU-heavy AAA games due to thread limitations
  • Requires a new motherboard (Socket LGA 1151) for those upgrading from older platforms
  • Does not include a stock CPU cooler in the box
  • Performance gains over previous-gen i5-4690K were considered modest at launch
  • Struggles with heavy multitasking and video rendering tasks compared to i7 models

Expert reviews

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expertreviews.co.uk
05/08/2015

The Intel Core i5-6600K (Skylake) is a 14nm quad-core processor offering strong, mid-range performance for gaming and productivity with improved per-clock efficiency over Haswell predecessors. It features excellent overclocking capabilities, with many units easily reaching 4.5GHz on air, alongside improved integrated Intel HD Graphics 530, making it a compelling, yet expensive,...Read more

D
digitalfoundry.net
21/10/2015

The 2015 Digital Foundry review identifies the Intel Core i5-6600K as a premier "default choice" for gaming, boasting improved IPC for superior performance in CPU-bound titles like The Witcher 3 and GTA 5. A significant advantage, or "pro," is the platform shift to the Z170 chipset and DDR4 memory, which delivers substantial performance gains, alongside excellent overclocking...Read more

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pcmag.com
12/10/2015

The Intel Core i5-6600K is a quad-core "Skylake" processor that PCMag highlights as a strong choice for price-conscious gamers and performance enthusiasts, offering a 3.5GHz base clock with an unlocked multiplier for easy overclocking. It excels in single-threaded tasks, often matching earlier Core i7 performance, while supporting modern chipset features like additional PCIe lanes...Read more

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guru3d.com
05/08/2015

The Guru3D review characterizes the Intel Core i5-6600K as a 14nm Skylake processor focusing on platform advancements, offering a 3.5 GHz base clock (3.9 GHz boost) and a modest 5-10% IPC improvement over Haswell. While raw CPU performance gains are limited, the Z170 platform provides key updates, including native DDR4 memory support, M.2 storage, and USB 3.1 connectivity. The chip...Read more

T
tomshardware.com
05/08/2015

Intel's Skylake architecture, featuring the Core i7-6700K and i5-6600K, transitions to a 14nm process node, a new LGA 1151 socket, and DDR4 memory, offering solid IPC gains over Haswell. The processors provide impressive multi-threaded performance and granular BCLK overclocking, though they require a complete platform overhaul. A key disadvantage noted is the underwhelming HD...Read more

M
m.hexus.net
11/08/2015

The Intel Core i5-6600K (14nm Skylake) is positioned as a sensible, overclockable choice for enthusiasts, offering 3.5GHz base/3.9GHz boost speeds and a strong performance-to-price ratio, though it lacks Hyper-Threading. While benchmarking shows an iterative 7-10% performance increase over Haswell, the platform's true advantages are support for DDR4 memory and the high-speed PCIe...Read more

G
gamestar.de
21/08/2015

The GameStar review identifies the Intel Core i5-6600K as the superior choice for gamers compared to the i7-6700K due to its high, overclockable performance on the Skylake architecture. Key advantages include strong single-core speed, an unlocked multiplier, and support for the modern Z170 platform with DDR4 memory, making it an excellent base for new systems. However, the 6600K...Read more

C
chip.de
01/09/2015

The Intel Core i5-6600K, reviewed on CHIP.de, is a solid 14nm Skylake processor offering high performance for mid-range gaming, with an unlocked multiplier that enables significant overclocking. Its main advantages include an excellent price-performance ratio compared to the i7-6700K and support for modern DDR4 memory on the LGA 1151/Z170 platform. However, the processor lacks...Read more

C
computerbase.de
05/08/2015

The 2015 ComputerBase review of Intel’s Skylake architecture highlights the Core i7-6700K and i5-6600K, focusing on the new LGA 1151 platform, DDR4 support, and improved IPC performance. While the i7-6700K offers strong 4.0 GHz performance, its clock speeds are lower than its predecessor, with the i5-6600K established as a solid high-end gaming choice without Hyper-Threading. Key...Read more

C
config-gamer.fr
28/08/2015

This Config-Gamer review evaluates the Intel Core i5-6600K (Skylake) against older CPUs (i5-4690K, i7-3770K, i5-2500K, FX-8350) using an overclocked Titan X at 1080p to isolate CPU performance. The Skylake i5-6600K provides a tangible performance boost over the i5-4690K at stock speeds, with up to a 17% increase in The Witcher 3 and matching previous-gen i7-4790K performance in some...Read more

O
overclocking.com
26/08/2015

The Intel Core i5-6600K is presented as a high-performance 14nm Skylake processor, featuring four cores, a 3.5 GHz base clock, and a fully unlocked multiplier for straightforward overclocking. It excels in gaming and single-core tasks, offering a modern, efficient alternative in late 2015 for users seeking strong performance on the LGA 1151 platform. Key pros include excellent...Read more

H
hardware.fr
05/08/2015

This 2015 review from Hardware.fr highlights Intel's architectural dominance during the transition to Skylake, with the Core i7-6700K and i5-6600K offering superior IPC and gaming performance, though hindered by high platform costs for new motherboards and DDR4 memory. Conversely, AMD struggled with its aging 32nm FX-series architecture, which, despite offering high thread counts,...Read more

H
hardware.fr
05/08/2015

The Hardware.fr review of the Intel Core i7-6700K and i5-6600K details the transition to the 14nm Skylake architecture and Z170 chipset, noting a modest ~10% performance increase over Haswell. Key platform changes include the removal of the FIVR, a mandatory shift to the LGA 1151 socket, and official support for DDR4 memory. Pros highlighted include improved, granular BCLK...Read more

C
comptoir-hardware.com
05/08/2015

The Comptoir-Hardware review of the Intel Z170 platform and Core i5-6600K highlights a significant, modernizing shift with the Skylake architecture. Key advantages include the native PCIe 3.0 lines on the Z170 chipset, supporting fast NVMe storage and USB 3.1, along with the adoption of DDR4 memory, though a notable downside is the requirement for a new LGA 1151 motherboard socket....Read more

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nl.hardware.info
05/08/2015

The Hardware.info review of Intel's 14nm Skylake architecture highlights the Core i7-6700K and i5-6600K, introducing the LGA 1151 socket, DDR4 support, and the Z170 chipset with 20 PCIe 3.0 lanes for improved connectivity. While offering a 10-25% performance boost in multi-threaded tasks over Haswell, the CPUs are deemed an evolutionary step, with the i5-6600K noted for high value...Read more

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