i5-6400 vs i5-8600K
Aggregate performance score
Core i5-8600K outperforms Core i5-6400 by an impressive 88% based on our aggregate benchmark results.
Primary details
Comparing Core i5-8600K and Core i5-6400 processor market type (desktop or notebook), architecture, sales start time and price.
| Place in the ranking | 1045 | 1547 |
| Place by popularity | not in top-100 | not in top-100 |
| Cost-effectiveness evaluation | 4.23 | 0.71 |
| Market segment | Desktop processor | Desktop processor |
| Series | Intel Core i5 | Intel Core i5 |
| Power efficiency | 6.40 | 4.97 |
| Architecture codename | Coffee Lake-S (2017−2018) | Skylake (2015−2016) |
| Release date | 24 September 2017 (7 years ago) | 1 September 2015 (9 years ago) |
| Launch price (MSRP) | $257 | $187 |
Cost-effectiveness evaluation
Performance per price, higher is better.
i5-8600K has 496% better value for money than i5-6400.
Detailed specifications
Core i5-8600K and Core i5-6400 basic parameters such as number of cores, number of threads, base frequency and turbo boost clock, lithography, cache size and multiplier lock state. These parameters indirectly say of CPU speed, though for more precise assessment you have to consider their test results.
| Physical cores | 6 (Hexa-Core) | 4 (Quad-Core) |
| Threads | 6 | 4 |
| Base clock speed | 3.6 GHz | 2.7 GHz |
| Boost clock speed | 4.3 GHz | 3.3 GHz |
| Bus type | DMI 3.0 | DMI 3.0 |
| Bus rate | 4 × 8 GT/s | 4 × 8 GT/s |
| Multiplier | 36 | 27 |
| L1 cache | 384 KB | 256 KB |
| L2 cache | 1.5 MB | 1 MB |
| L3 cache | 9 MB (shared) | 6 MB (shared) |
| Chip lithography | 14 nm | 14 nm |
| Die size | 149 mm2 | 122 mm2 |
| Maximum core temperature | 100 °C | no data |
| Maximum case temperature (TCase) | 72 °C | 72 °C |
| 64 bit support | + | + |
| Windows 11 compatibility | + | - |
| Unlocked multiplier | + | - |
Compatibility
Information on Core i5-8600K and Core i5-6400 compatibility with other computer components: motherboard (look for socket type), power supply unit (look for power consumption) etc. Useful when planning a future computer configuration or upgrading an existing one. Note that power consumption of some processors can well exceed their nominal TDP, even without overclocking. Some can even double their declared thermals given that the motherboard allows to tune the CPU power parameters.
| Number of CPUs in a configuration | 1 (Uniprocessor) | 1 (Uniprocessor) |
| Socket | FCLGA1151 | FCLGA1151 |
| Power consumption (TDP) | 95 Watt | 65 Watt |
Technologies and extensions
Technological solutions and additional instructions supported by Core i5-8600K and Core i5-6400. You'll probably need this information if you require some particular technology.
| Instruction set extensions | Intel® SSE4.1, Intel® SSE4.2, Intel® AVX2 | Intel® SSE4.1, Intel® SSE4.2, Intel® AVX2 |
| AES-NI | + | + |
| AVX | + | + |
| vPro | + | + |
| Enhanced SpeedStep (EIST) | + | + |
| Turbo Boost Technology | 2.0 | 2.0 |
| Hyper-Threading Technology | + | - |
| TSX | + | - |
| Idle States | + | + |
| Thermal Monitoring | + | + |
| SIPP | + | - |
Security technologies
Core i5-8600K and Core i5-6400 technologies aimed at improving security, for example, by protecting against hacks.
| TXT | + | - |
| EDB | + | + |
| Secure Key | + | + |
| MPX | + | + |
| Identity Protection | + | + |
| SGX | Yes with Intel® ME | Yes with Intel® ME |
| OS Guard | + | + |
Virtualization technologies
Virtual machine speed-up technologies supported by Core i5-8600K and Core i5-6400 are enumerated here.
| AMD-V | + | + |
| VT-d | + | + |
| VT-x | + | + |
| EPT | + | + |
Memory specs
Types, maximum amount and channel quantity of RAM supported by Core i5-8600K and Core i5-6400. Depending on the motherboard, higher memory frequencies may be supported.
| Supported memory types | DDR3, DDR4 | DDR3, DDR4 |
| Maximum memory size | 128 GB | 64 GB |
| Max memory channels | 2 | 2 |
| Maximum memory bandwidth | 42.671 GB/s | 34.134 GB/s |
Graphics specifications
General parameters of integrated GPUs, if any.
| Integrated graphics card Compare | Intel UHD Graphics 630 | Intel HD Graphics 530 |
| Max video memory | 64 GB | 64 GB |
| Quick Sync Video | + | + |
| Clear Video | + | + |
| Clear Video HD | + | + |
| Graphics max frequency | 1.15 GHz | 950 MHz |
| InTru 3D | + | + |
Graphics interfaces
Available interfaces and connections of Core i5-8600K and Core i5-6400 integrated GPUs.
| Number of displays supported | 3 | 3 |
| eDP | no data | + |
| DisplayPort | - | + |
| HDMI | - | + |
| DVI | no data | + |
Graphics image quality
Maximum display resolutions supported by Core i5-8600K and Core i5-6400 integrated GPUs, including resolutions over different interfaces.
| 4K resolution support | + | + |
| Max resolution over HDMI 1.4 | 4096x2304@24Hz | 4096x2304@24Hz |
| Max resolution over eDP | 4096x2304@60Hz | 4096x2304@60Hz |
| Max resolution over DisplayPort | 4096x2304@60Hz | 4096x2304@60Hz |
| Max resolution over VGA | no data | N/A |
Graphics API support
APIs supported by Core i5-8600K and Core i5-6400 integrated GPUs, sometimes API versions are included.
| DirectX | 12 | 12 |
| OpenGL | 4.5 | 4.5 |
Peripherals
Specifications and connection of peripherals supported by Core i5-8600K and Core i5-6400.
| PCIe version | 3.0 | 3.0 |
| PCI Express lanes | 16 | 16 |
Synthetic benchmark performance
Various benchmark results of the processors in comparison. Overall score is measured in points in 0-100 range, higher is better.
Combined synthetic benchmark score
This is our combined benchmark performance rating. We are regularly improving our combining algorithms, but if you find some perceived inconsistencies, feel free to speak up in comments section, we usually fix problems quickly.
Passmark
Passmark CPU Mark is a widespread benchmark, consisting of 8 different types of workload, including integer and floating point math, extended instructions, compression, encryption and physics calculation. There is also one separate single-threaded scenario measuring single-core performance.
GeekBench 5 Single-Core
GeekBench 5 Single-Core is a cross-platform application developed in the form of CPU tests that independently recreate certain real-world tasks with which to accurately measure performance. This version uses only a single CPU core.
GeekBench 5 Multi-Core
GeekBench 5 Multi-Core is a cross-platform application developed in the form of CPU tests that independently recreate certain real-world tasks with which to accurately measure performance. This version uses all available CPU cores.
Cinebench 10 32-bit single-core
Cinebench R10 is an ancient ray tracing benchmark for processors by Maxon, authors of Cinema 4D. Its single core version uses just one CPU thread to render a futuristic looking motorcycle.
Cinebench 10 32-bit multi-core
Cinebench Release 10 Multi Core is a variant of Cinebench R10 using all the processor threads. Possible number of threads is limited by 16 in this version.
wPrime 32
wPrime 32M is a math multi-thread processor test, which calculates square roots of first 32 million integer numbers. Its result is measured in seconds, so that the less is benchmark result, the faster the processor.
Cinebench 11.5 64-bit multi-core
Cinebench Release 11.5 Multi Core is a variant of Cinebench R11.5 which uses all the processor threads. A maximum of 64 threads is supported in this version.
Cinebench 15 64-bit multi-core
Cinebench Release 15 Multi Core is a variant of Cinebench R15 which uses all the processor threads.
Cinebench 15 64-bit single-core
Cinebench R15 (standing for Release 15) is a benchmark made by Maxon, authors of Cinema 4D. It was superseded by later versions of Cinebench, which use more modern variants of Cinema 4D engine. The Single Core version (sometimes called Single-Thread) only uses a single processor thread to render a room full of reflective spheres and light sources.
Cinebench 11.5 64-bit single-core
Cinebench R11.5 is an old benchmark by Maxon, authors of Cinema 4D. It was superseded by later versions of Cinebench, which use more modern variants of Cinema 4D engine. The Single Core version loads a single thread with ray tracing to render a glossy room full of crystal spheres and light sources.
TrueCrypt AES
TrueCrypt is a discontinued piece of software that was widely used for on-the-fly-encryption of disk partitions, now superseded by VeraCrypt. It contains several embedded performance tests, one of them being TrueCrypt AES, which measures data encryption speed using AES algorithm. Result is encryption speed in gigabytes per second.
x264 encoding pass 2
x264 Pass 2 is a slower variant of x264 video compression that produces a variable bit rate output file, which results in better quality since the higher bit rate is used when it is needed more. Benchmark result is still measured in frames per second.
x264 encoding pass 1
x264 version 4.0 is a video encoding benchmark uses MPEG 4 x264 compression method to compress a sample HD (720p) video. Pass 1 is a faster variant that produces a constant bit rate output file. Its result is measured in frames per second, which means how many frames of the source video file were encoded per second.
Pros & cons summary
| Performance score | 6.67 | 3.54 |
| Integrated graphics card | 3.09 | 2.59 |
| Recency | 24 September 2017 | 1 September 2015 |
| Physical cores | 6 | 4 |
| Threads | 6 | 4 |
| Power consumption (TDP) | 95 Watt | 65 Watt |
i5-8600K has a 88.4% higher aggregate performance score, 19.3% faster integrated GPU, an age advantage of 2 years, and 50% more physical cores and 50% more threads.
i5-6400, on the other hand, has 46.2% lower power consumption.
The Core i5-8600K is our recommended choice as it beats the Core i5-6400 in performance tests.
Should you still have questions on choice between Core i5-8600K and Core i5-6400, ask them in Comments section, and we shall answer.
Similar processor comparisons
We picked several similar comparisons of processors in the same market segment and performance relatively close to those reviewed on this page.
