FX-8120 vs Ryzen 9 3900
Aggregate performance score
Ryzen 9 3900 outperforms FX-8120 by a whopping 367% based on our aggregate benchmark results.
Primary details
Comparing Ryzen 9 3900 and FX-8120 processor market type (desktop or notebook), architecture, sales start time and price.
| Place in the ranking | 290 | 1384 |
| Place by popularity | not in top-100 | not in top-100 |
| Cost-effectiveness evaluation | 20.03 | no data |
| Market segment | Desktop processor | Desktop processor |
| Series | AMD Matisse (Ryzen 3000 Desktop) | no data |
| Power efficiency | 28.23 | 3.14 |
| Architecture codename | Matisse (Zen 2) (2019−2020) | Zambezi (2011−2012) |
| Release date | 24 September 2019 (5 years ago) | 12 October 2011 (13 years ago) |
| Launch price (MSRP) | $499 | no data |
Cost-effectiveness evaluation
Performance per price, higher is better.
Detailed specifications
Ryzen 9 3900 and FX-8120 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) | 8 (Octa-Core) |
| Threads | 24 | 8 |
| Base clock speed | 3.1 GHz | 3.1 GHz |
| Boost clock speed | 4.3 GHz | 4 GHz |
| L1 cache | 64 KB (per core) | 384 KB |
| L2 cache | 512 KB (per core) | 8192 KB |
| L3 cache | 64 MB | 8192 KB |
| Chip lithography | 7 nm, 12 nm | 32 nm |
| Die size | 2x 74 mm2 | 315 mm2 |
| Maximum core temperature | no data | 61 °C |
| Number of transistors | 7,600 million | 1,200 million |
| 64 bit support | + | + |
| Windows 11 compatibility | - | - |
| Unlocked multiplier | + | + |
| P0 Vcore voltage | no data | Min: 1.0125 V - Max: 1.4125 V |
Compatibility
Information on Ryzen 9 3900 and FX-8120 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 | 1 |
| Socket | AM4 | AM3+ |
| Power consumption (TDP) | 65 Watt | 125 Watt |
Technologies and extensions
Technological solutions and additional instructions supported by Ryzen 9 3900 and FX-8120. You'll probably need this information if you require some particular technology.
| Instruction set extensions | 86x MMX(+), SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, SSE4A,-64, AMD-V, AES, AVX, AVX2, FMA3, SHA, Precision Boost 2 | no data |
| AES-NI | + | + |
| FMA | - | + |
| AVX | + | + |
| Precision Boost 2 | + | no data |
Virtualization technologies
Virtual machine speed-up technologies supported by Ryzen 9 3900 and FX-8120 are enumerated here.
| AMD-V | + | + |
Memory specs
Types, maximum amount and channel quantity of RAM supported by Ryzen 9 3900 and FX-8120. Depending on the motherboard, higher memory frequencies may be supported.
| Supported memory types | DDR4-3200 | DDR3 |
| Maximum memory size | 128 GB | no data |
| Max memory channels | 2 | no data |
| Maximum memory bandwidth | 51.196 GB/s | no data |
Graphics specifications
General parameters of integrated GPUs, if any.
| Integrated graphics card | N/A | no data |
Peripherals
Specifications and connection of peripherals supported by Ryzen 9 3900 and FX-8120.
| PCIe version | 4.0 | n/a |
| PCI Express lanes | 24 | no data |
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 | 19.39 | 4.15 |
| Recency | 24 September 2019 | 12 October 2011 |
| Physical cores | 12 | 8 |
| Threads | 24 | 8 |
| Chip lithography | 7 nm | 32 nm |
| Power consumption (TDP) | 65 Watt | 125 Watt |
Ryzen 9 3900 has a 367.2% higher aggregate performance score, an age advantage of 7 years, 50% more physical cores and 200% more threads, a 357.1% more advanced lithography process, and 92.3% lower power consumption.
The Ryzen 9 3900 is our recommended choice as it beats the FX-8120 in performance tests.
Should you still have questions on choice between Ryzen 9 3900 and FX-8120, ask them in Comments section, and we shall answer.
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