Ryzen 9 5900X vs Athlon II X4 645
Aggregate performance score
Ryzen 9 5900X outperforms Athlon II X4 645 by a whopping 1571% based on our aggregate benchmark results.
Primary details
Comparing Athlon II X4 645 and Ryzen 9 5900X processor market type (desktop or notebook), architecture, sales start time and price.
| Place in the ranking | 2149 | 199 |
| Place by popularity | not in top-100 | not in top-100 |
| Cost-effectiveness evaluation | 3.30 | 31.05 |
| Market segment | Desktop processor | Desktop processor |
| Series | no data | AMD Ryzen 9 |
| Power efficiency | 1.47 | 22.20 |
| Architecture codename | Propus (2009−2011) | Vermeer (Zen3) (2020−2022) |
| Release date | 21 September 2010 (14 years ago) | 8 October 2020 (4 years ago) |
| Launch price (MSRP) | $80 | $549 |
Cost-effectiveness evaluation
Performance per price, higher is better.
Ryzen 9 5900X has 841% better value for money than Athlon II X4 645.
Detailed specifications
Athlon II X4 645 and Ryzen 9 5900X 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) | 12 (Dodeca-Core) |
| Threads | 4 | 24 |
| Base clock speed | 3.1 GHz | 3.7 GHz |
| Boost clock speed | 3.1 GHz | 4.8 GHz |
| Multiplier | no data | 37 |
| L1 cache | 128 KB (per core) | 768 KB |
| L2 cache | 512 KB (per core) | 6 MB |
| L3 cache | 0 KB | 64 MB |
| Chip lithography | 45 nm | 7 nm, 12 nm |
| Die size | 169 mm2 | 2x 74 mm2(CCD) + 125 mm2 (IOD) |
| Maximum case temperature (TCase) | no data | 95 °C |
| Number of transistors | 300 million | 0 Million |
| 64 bit support | + | + |
| Windows 11 compatibility | - | + |
| Unlocked multiplier | - | + |
Compatibility
Information on Athlon II X4 645 and Ryzen 9 5900X 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 | AM3 | AM4 |
| Power consumption (TDP) | 95 Watt | 105 Watt |
Technologies and extensions
Technological solutions and additional instructions supported by Athlon II X4 645 and Ryzen 9 5900X. You'll probably need this information if you require some particular technology.
| Instruction set extensions | no data | 86x MMX(+), SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, SSE4A,-64, AMD-V, AES, AVX, AVX2, FMA3, SHA, Precision Boost 2 |
| AES-NI | - | + |
| AVX | - | + |
| Precision Boost 2 | no data | + |
Virtualization technologies
Virtual machine speed-up technologies supported by Athlon II X4 645 and Ryzen 9 5900X are enumerated here.
| AMD-V | - | + |
Memory specs
Types, maximum amount and channel quantity of RAM supported by Athlon II X4 645 and Ryzen 9 5900X. Depending on the motherboard, higher memory frequencies may be supported.
| Supported memory types | DDR3 | DDR4-3200 |
| Maximum memory size | no data | 128 GB |
| Max memory channels | no data | 2 |
| Maximum memory bandwidth | no data | 51.196 GB/s |
Peripherals
Specifications and connection of peripherals supported by Athlon II X4 645 and Ryzen 9 5900X.
| PCIe version | 2.0 | 4.0 |
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 | 1.53 | 25.56 |
| Recency | 21 September 2010 | 8 October 2020 |
| Physical cores | 4 | 12 |
| Threads | 4 | 24 |
| Chip lithography | 45 nm | 7 nm |
| Power consumption (TDP) | 95 Watt | 105 Watt |
Athlon II X4 645 has 10.5% lower power consumption.
Ryzen 9 5900X, on the other hand, has a 1570.6% higher aggregate performance score, an age advantage of 10 years, 200% more physical cores and 500% more threads, and a 542.9% more advanced lithography process.
The Ryzen 9 5900X is our recommended choice as it beats the Athlon II X4 645 in performance tests.
Should you still have questions on choice between Athlon II X4 645 and Ryzen 9 5900X, ask them in Comments section, and we shall answer.
Similar processor comparisons
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