EPYC 7643 vs Ryzen 9 3900X
Aggregate performance score
EPYC 7643 outperforms Ryzen 9 3900X by a whopping 133% based on our aggregate benchmark results.
Primary details
Comparing Ryzen 9 3900X and EPYC 7643 processor market type (desktop or notebook), architecture, sales start time and price.
| Place in the ranking | 264 | 38 |
| Place by popularity | not in top-100 | not in top-100 |
| Cost-effectiveness evaluation | 22.06 | 6.58 |
| Market segment | Desktop processor | Server |
| Series | AMD Ryzen 9 | AMD EPYC |
| Power efficiency | 18.51 | 20.14 |
| Architecture codename | Matisse (Zen 2) (2019−2020) | Milan (2021−2023) |
| Release date | 7 July 2019 (5 years ago) | 12 January 2021 (3 years ago) |
| Launch price (MSRP) | $499 | $4,995 |
Cost-effectiveness evaluation
Performance per price, higher is better.
Ryzen 9 3900X has 235% better value for money than EPYC 7643.
Detailed specifications
Ryzen 9 3900X and EPYC 7643 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 | 12 (Dodeca-Core) | 48 (Octatetraconta-Core) |
| Threads | 24 | 96 |
| Base clock speed | 3.8 GHz | 2.3 GHz |
| Boost clock speed | 4.6 GHz | 3.6 GHz |
| Multiplier | no data | 23 |
| L1 cache | 768 KB | 3 MB |
| L2 cache | 6 MB | 24 MB |
| L3 cache | 64 MB | 256 MB (shared) |
| Chip lithography | 7 nm, 12 nm | 7 nm+ |
| Die size | no data | 8x 81 mm2 |
| Maximum core temperature | 95 °C | no data |
| Number of transistors | 19,200 million | 33,200 million |
| 64 bit support | + | + |
| Windows 11 compatibility | + | + |
| Unlocked multiplier | + | - |
Compatibility
Information on Ryzen 9 3900X and EPYC 7643 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 |
| Socket | AM4 | SP3 |
| Power consumption (TDP) | 105 Watt | 225 Watt |
Technologies and extensions
Technological solutions and additional instructions supported by Ryzen 9 3900X and EPYC 7643. You'll probably need this information if you require some particular technology.
| AES-NI | + | + |
| AVX | + | + |
| Precision Boost 2 | + | no data |
Virtualization technologies
Virtual machine speed-up technologies supported by Ryzen 9 3900X and EPYC 7643 are enumerated here.
| AMD-V | + | + |
Memory specs
Types, maximum amount and channel quantity of RAM supported by Ryzen 9 3900X and EPYC 7643. Depending on the motherboard, higher memory frequencies may be supported.
| Supported memory types | DDR4 Dual-channel | DDR4-3200 |
| Maximum memory size | 128 GB | 4 TiB |
| Max memory channels | 2 | no data |
| Maximum memory bandwidth | 51.196 GB/s | 204.795 GB/s |
Graphics specifications
General parameters of integrated GPUs, if any.
| Integrated graphics card | - | N/A |
Peripherals
Specifications and connection of peripherals supported by Ryzen 9 3900X and EPYC 7643.
| PCIe version | no data | 4.0 |
| PCI Express lanes | no data | 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.
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 | 21.36 | 49.80 |
| Recency | 7 July 2019 | 12 January 2021 |
| Physical cores | 12 | 48 |
| Threads | 24 | 96 |
| Power consumption (TDP) | 105 Watt | 225 Watt |
Ryzen 9 3900X has 114.3% lower power consumption.
EPYC 7643, on the other hand, has a 133.1% higher aggregate performance score, an age advantage of 1 year, and 300% more physical cores and 300% more threads.
The EPYC 7643 is our recommended choice as it beats the Ryzen 9 3900X in performance tests.
Note that Ryzen 9 3900X is a desktop processor while EPYC 7643 is a server/workstation one.
Should you still have questions on choice between Ryzen 9 3900X and EPYC 7643, 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.
