i9-7900X vs i9-7940X
Aggregate performance score
Core i9-7940X outperforms Core i9-7900X by a significant 23% based on our aggregate benchmark results.
Primary details
Comparing Core i9-7940X and Core i9-7900X processor market type (desktop or notebook), architecture, sales start time and price.
| Place in the ranking | 408 | 568 |
| Place by popularity | not in top-100 | not in top-100 |
| Cost-effectiveness evaluation | 3.30 | 2.96 |
| Market segment | Desktop processor | Desktop processor |
| Series | Intel Core i9 | Core i9 (Desktop) |
| Power efficiency | 9.37 | 8.96 |
| Architecture codename | Skylake (server) (2017−2018) | Skylake (server) (2017−2018) |
| Release date | 30 May 2017 (7 years ago) | 30 May 2017 (7 years ago) |
| Launch price (MSRP) | $1,399 | $999 |
Cost-effectiveness evaluation
Performance per price, higher is better.
i9-7940X has 11% better value for money than i9-7900X.
Detailed specifications
Core i9-7940X and Core i9-7900X 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 | 14 (Tetradeca-Core) | 10 (Deca-Core) |
| Threads | 28 | 20 |
| Base clock speed | 3.1 GHz | 3.3 GHz |
| Boost clock speed | 4.4 GHz | 4.5 GHz |
| Bus type | DMI 3.0 | DMI 3.0 |
| Bus rate | 4 × 8 GT/s | 4 × 8 GT/s |
| Multiplier | no data | 33 |
| L1 cache | 896 KB | 640 KB |
| L2 cache | 14 MB | 10 MB |
| L3 cache | 19.25 MB (shared) | 13.75 MB |
| Chip lithography | 14 nm | 14 nm |
| Die size | 484 mm2 | no data |
| Maximum core temperature | 102 °C | 95 °C |
| Maximum case temperature (TCase) | no data | 72 °C |
| 64 bit support | + | + |
| Windows 11 compatibility | + | + |
| Unlocked multiplier | + | + |
Compatibility
Information on Core i9-7940X and Core i9-7900X 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 | FCLGA2066 | Socket R4 |
| Power consumption (TDP) | 165 Watt | 140 Watt |
Technologies and extensions
Technological solutions and additional instructions supported by Core i9-7940X and Core i9-7900X. You'll probably need this information if you require some particular technology.
| Instruction set extensions | Intel® SSE4.1, Intel® SSE4.2, Intel® AVX2, Intel® AVX-512 | Intel® SSE4.1, Intel® SSE4.2, Intel® AVX2, Intel® AVX-512 |
| AES-NI | + | + |
| AVX | + | + |
| vPro | no data | + |
| Enhanced SpeedStep (EIST) | + | + |
| Turbo Boost Technology | 2.0 | 2.0 |
| Hyper-Threading Technology | + | + |
| TSX | + | + |
| Turbo Boost Max 3.0 | + | + |
Security technologies
Core i9-7940X and Core i9-7900X technologies aimed at improving security, for example, by protecting against hacks.
| EDB | + | + |
Virtualization technologies
Virtual machine speed-up technologies supported by Core i9-7940X and Core i9-7900X are enumerated here.
| AMD-V | - | + |
| VT-d | + | + |
| VT-x | + | + |
Memory specs
Types, maximum amount and channel quantity of RAM supported by Core i9-7940X and Core i9-7900X. Depending on the motherboard, higher memory frequencies may be supported.
| Supported memory types | DDR4-2666 | DDR4 |
| Maximum memory size | 128 GB | 128 GB |
| Max memory channels | 4 | 4 |
| Maximum memory bandwidth | 85.33 GB/s | 85.33 GB/s |
Graphics specifications
General parameters of integrated GPUs, if any.
| Integrated graphics card | N/A | N/A |
Peripherals
Specifications and connection of peripherals supported by Core i9-7940X and Core i9-7900X.
| PCIe version | 3.0 | 3.0 |
| PCI Express lanes | 44 | 44 |
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.
Pros & cons summary
| Performance score | 16.34 | 13.25 |
| Physical cores | 14 | 10 |
| Threads | 28 | 20 |
| Power consumption (TDP) | 165 Watt | 140 Watt |
i9-7940X has a 23.3% higher aggregate performance score, and 40% more physical cores and 40% more threads.
i9-7900X, on the other hand, has 17.9% lower power consumption.
The Core i9-7940X is our recommended choice as it beats the Core i9-7900X in performance tests.
Should you still have questions on choice between Core i9-7940X and Core i9-7900X, ask them in Comments section, and we shall answer.
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