Ryzen 9 7945HX3D vs Ryzen 9 3900
Aggregate performance score
Ryzen 9 7945HX3D outperforms Ryzen 9 3900 by an impressive 88% based on our aggregate benchmark results.
Primary details
Comparing Ryzen 9 3900 and Ryzen 9 7945HX3D processor market type (desktop or notebook), architecture, sales start time and price.
| Place in the ranking | 289 | 97 |
| Place by popularity | not in top-100 | not in top-100 |
| Cost-effectiveness evaluation | 19.98 | no data |
| Market segment | Desktop processor | Laptop |
| Series | AMD Matisse (Ryzen 3000 Desktop) | AMD Dragon Range (Zen 4, Ryzen 7045) |
| Power efficiency | 28.23 | 62.70 |
| Architecture codename | Matisse (Zen 2) (2019−2020) | Dragon Range-HX (Zen 4) (2023−2024) |
| Release date | 24 September 2019 (5 years ago) | 27 July 2023 (1 year ago) |
| Launch price (MSRP) | $499 | no data |
Cost-effectiveness evaluation
Performance per price, higher is better.
Detailed specifications
Ryzen 9 3900 and Ryzen 9 7945HX3D 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) | 16 (Hexadeca-Core) |
| Threads | 24 | 32 |
| Base clock speed | 3.1 GHz | 2.3 GHz |
| Boost clock speed | 4.3 GHz | 5.4 GHz |
| L1 cache | 64 KB (per core) | 64 KB (per core) |
| L2 cache | 512 KB (per core) | 1 MB (per core) |
| L3 cache | 64 MB | 128 MB (shared) |
| Chip lithography | 7 nm, 12 nm | 5 nm |
| Die size | 2x 74 mm2 | 2x 71 mm2 |
| Maximum core temperature | no data | 89 °C |
| Number of transistors | 7,600 million | 17,840 million |
| 64 bit support | + | + |
| Windows 11 compatibility | - | no data |
| Unlocked multiplier | + | + |
Compatibility
Information on Ryzen 9 3900 and Ryzen 9 7945HX3D 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 | FL1 |
| Power consumption (TDP) | 65 Watt | 55 Watt |
Technologies and extensions
Technological solutions and additional instructions supported by Ryzen 9 3900 and Ryzen 9 7945HX3D. 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 | + | + |
| AVX | + | + |
| Precision Boost 2 | + | + |
Virtualization technologies
Virtual machine speed-up technologies supported by Ryzen 9 3900 and Ryzen 9 7945HX3D are enumerated here.
| AMD-V | + | + |
Memory specs
Types, maximum amount and channel quantity of RAM supported by Ryzen 9 3900 and Ryzen 9 7945HX3D. Depending on the motherboard, higher memory frequencies may be supported.
| Supported memory types | DDR4-3200 | DDR5-5200 |
| 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 | AMD Radeon 610M |
Peripherals
Specifications and connection of peripherals supported by Ryzen 9 3900 and Ryzen 9 7945HX3D.
| PCIe version | 4.0 | 5.0 |
| PCI Express lanes | 24 | 28 |
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.
Cinebench 10 32-bit single-core
Cinebench R10 is an ancient ray tracing benchmark for processors by Maxon, authors of Cinema 4D. Its single core version uses just one CPU thread to render a futuristic looking motorcycle.
Cinebench 10 32-bit multi-core
Cinebench Release 10 Multi Core is a variant of Cinebench R10 using all the processor threads. Possible number of threads is limited by 16 in this version.
Cinebench 11.5 64-bit multi-core
Cinebench Release 11.5 Multi Core is a variant of Cinebench R11.5 which uses all the processor threads. A maximum of 64 threads is supported in this version.
Cinebench 15 64-bit multi-core
Cinebench Release 15 Multi Core is a variant of Cinebench R15 which uses all the processor threads.
Cinebench 15 64-bit single-core
Cinebench R15 (standing for Release 15) is a benchmark made by Maxon, authors of Cinema 4D. It was superseded by later versions of Cinebench, which use more modern variants of Cinema 4D engine. The Single Core version (sometimes called Single-Thread) only uses a single processor thread to render a room full of reflective spheres and light sources.
Cinebench 11.5 64-bit single-core
Cinebench R11.5 is an old benchmark by Maxon, authors of Cinema 4D. It was superseded by later versions of Cinebench, which use more modern variants of Cinema 4D engine. The Single Core version loads a single thread with ray tracing to render a glossy room full of crystal spheres and light sources.
TrueCrypt AES
TrueCrypt is a discontinued piece of software that was widely used for on-the-fly-encryption of disk partitions, now superseded by VeraCrypt. It contains several embedded performance tests, one of them being TrueCrypt AES, which measures data encryption speed using AES algorithm. Result is encryption speed in gigabytes per second.
WinRAR 4.0
WinRAR 4.0 is an outdated version of a popular file archiver. It contains an internal speed test, using 'Best' setting of RAR compression on large chunks of randomly generated data. Its results are measured in kilobytes per second.
Geekbench 5.5 Multi-Core
Blender(-)
Geekbench 5.5 Single-Core
7-Zip Single
7-Zip
WebXPRT 3
Pros & cons summary
| Performance score | 19.39 | 36.44 |
| Recency | 24 September 2019 | 27 July 2023 |
| Physical cores | 12 | 16 |
| Threads | 24 | 32 |
| Chip lithography | 7 nm | 5 nm |
| Power consumption (TDP) | 65 Watt | 55 Watt |
Ryzen 9 7945HX3D has a 87.9% higher aggregate performance score, an age advantage of 3 years, 33.3% more physical cores and 33.3% more threads, a 40% more advanced lithography process, and 18.2% lower power consumption.
The Ryzen 9 7945HX3D is our recommended choice as it beats the Ryzen 9 3900 in performance tests.
Note that Ryzen 9 3900 is a desktop processor while Ryzen 9 7945HX3D is a notebook one.
Should you still have questions on choice between Ryzen 9 3900 and Ryzen 9 7945HX3D, ask them in Comments section, and we shall answer.
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