EPYC 7251 vs i5-6600K
Aggregate performance score
EPYC 7251 outperforms Core i5-6600K by a whopping 136% based on our aggregate benchmark results.
Primary details
Comparing Core i5-6600K and EPYC 7251 processor market type (desktop or notebook), architecture, sales start time and price.
| Place in the ranking | 1414 | 803 |
| Place by popularity | not in top-100 | not in top-100 |
| Cost-effectiveness evaluation | 0.77 | 3.03 |
| Market segment | Desktop processor | Server |
| Series | Intel Core i5 (Desktop) | AMD EPYC |
| Power efficiency | 4.14 | 7.42 |
| Architecture codename | Skylake (2015−2016) | Naples (2017−2018) |
| Release date | 5 August 2015 (9 years ago) | 29 June 2017 (7 years ago) |
| Launch price (MSRP) | $242 | $574 |
Cost-effectiveness evaluation
Performance per price, higher is better.
EPYC 7251 has 294% better value for money than i5-6600K.
Detailed specifications
Core i5-6600K and EPYC 7251 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 | 4 (Quad-Core) | 8 (Octa-Core) |
| Threads | 4 | 16 |
| Base clock speed | 3.5 GHz | 2.1 GHz |
| Boost clock speed | 3.9 GHz | 2.9 GHz |
| Bus type | DMI 3.0 | no data |
| Bus rate | 4 × 8 GT/s | no data |
| Multiplier | 35 | 21 |
| L1 cache | 64 KB (per core) | 96K (per core) |
| L2 cache | 256 KB (per core) | 512K (per core) |
| L3 cache | 6 MB (shared) | 32 MB (shared) |
| Chip lithography | 14 nm | 14 nm |
| Die size | 122 mm2 | 192 mm2 |
| Maximum case temperature (TCase) | 64 °C | no data |
| Number of transistors | no data | 4,800 million |
| 64 bit support | + | + |
| Windows 11 compatibility | - | - |
| Unlocked multiplier | + | + |
Compatibility
Information on Core i5-6600K and EPYC 7251 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) | 2 (Multiprocessor) |
| Socket | FCLGA1151 | TR4 |
| Power consumption (TDP) | 91 Watt | 120 Watt |
Technologies and extensions
Technological solutions and additional instructions supported by Core i5-6600K and EPYC 7251. You'll probably need this information if you require some particular technology.
| Instruction set extensions | Intel® SSE4.1, Intel® SSE4.2, Intel® AVX2 | no data |
| AES-NI | + | + |
| AVX | + | + |
| vPro | + | no data |
| Enhanced SpeedStep (EIST) | + | no data |
| Turbo Boost Technology | 2.0 | no data |
| Hyper-Threading Technology | - | no data |
| TSX | + | - |
| Idle States | + | no data |
| Thermal Monitoring | + | - |
Security technologies
Core i5-6600K and EPYC 7251 technologies aimed at improving security, for example, by protecting against hacks.
| TXT | - | no data |
| EDB | + | no data |
| Secure Key | + | no data |
| MPX | + | - |
| Identity Protection | + | - |
| SGX | Yes with Intel® ME | no data |
| OS Guard | + | no data |
Virtualization technologies
Virtual machine speed-up technologies supported by Core i5-6600K and EPYC 7251 are enumerated here.
| AMD-V | + | + |
| VT-d | + | no data |
| VT-x | + | no data |
| EPT | + | no data |
Memory specs
Types, maximum amount and channel quantity of RAM supported by Core i5-6600K and EPYC 7251. Depending on the motherboard, higher memory frequencies may be supported.
| Supported memory types | DDR3, DDR4 | DDR4 Eight-channel |
| Maximum memory size | 64 GB | 2 TiB |
| Max memory channels | 2 | 8 |
| Maximum memory bandwidth | 34.134 GB/s | 153.652 GB/s |
| ECC memory support | - | + |
Graphics specifications
General parameters of integrated GPUs, if any.
| Integrated graphics card | Intel HD Graphics 530 | no data |
| Max video memory | 64 GB | no data |
| Quick Sync Video | + | - |
| Clear Video | + | no data |
| Clear Video HD | + | no data |
| Graphics max frequency | 1.15 GHz | no data |
| InTru 3D | + | no data |
Graphics interfaces
Available interfaces and connections of Core i5-6600K and EPYC 7251 integrated GPUs.
| Number of displays supported | 3 | no data |
| eDP | + | no data |
| DisplayPort | + | - |
| HDMI | + | - |
| DVI | + | no data |
Graphics image quality
Maximum display resolutions supported by Core i5-6600K and EPYC 7251 integrated GPUs, including resolutions over different interfaces.
| 4K resolution support | + | no data |
| Max resolution over HDMI 1.4 | 4096x2304@24Hz | no data |
| Max resolution over eDP | 4096x2304@60Hz | no data |
| Max resolution over DisplayPort | 4096x2304@60Hz | no data |
| Max resolution over VGA | N/A | no data |
Graphics API support
APIs supported by Core i5-6600K and EPYC 7251 integrated GPUs, sometimes API versions are included.
| DirectX | 12 | no data |
| OpenGL | 4.5 | no data |
Peripherals
Specifications and connection of peripherals supported by Core i5-6600K and EPYC 7251.
| PCIe version | 3.0 | 3.0 |
| PCI Express lanes | 16 | 128 |
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.
Pros & cons summary
| Performance score | 4.13 | 9.76 |
| Recency | 5 August 2015 | 29 June 2017 |
| Physical cores | 4 | 8 |
| Threads | 4 | 16 |
| Power consumption (TDP) | 91 Watt | 120 Watt |
i5-6600K has 31.9% lower power consumption.
EPYC 7251, on the other hand, has a 136.3% higher aggregate performance score, an age advantage of 1 year, and 100% more physical cores and 300% more threads.
The EPYC 7251 is our recommended choice as it beats the Core i5-6600K in performance tests.
Note that Core i5-6600K is a desktop processor while EPYC 7251 is a server/workstation one.
Should you still have questions on choice between Core i5-6600K and EPYC 7251, ask them in Comments section, and we shall answer.
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