Ryzen 9 7945HX vs Ryzen 9 3900
Aggregated performance score
Ryzen 9 7945HX outperforms Ryzen 9 3900 by an impressive 78% based on our aggregated benchmark results.
Primary details
Comparing Ryzen 9 3900 and Ryzen 9 7945HX processor market type (desktop or notebook), architecture, sales start time and price.
| Place in performance ranking | 248 | 87 |
| Place by popularity | not in top-100 | not in top-100 |
| Cost-effectiveness evaluation | 35.57 | no data |
| Market segment | Desktop processor | Laptop |
| Series | AMD Matisse (Ryzen 3000 Desktop) | no data |
| Architecture codename | Matisse (Zen 2) (2019−2020) | Dragon Range-HX (Zen 4) |
| Release date | 9 October 2019 (4 years ago) | 4 January 2023 (1 year ago) |
| Current price | $381 | no data |
Cost-effectiveness evaluation
Performance per price, higher is better.
Detailed specifications
Ryzen 9 3900 and Ryzen 9 7945HX 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 | 2.5 GHz |
| Boost clock speed | 4.3 GHz | 5.4 GHz |
| L1 cache | 768 KB | 64K (per core) |
| L2 cache | 6 MB | 1 MB (per core) |
| L3 cache | 64 MB | 64 MB (shared) |
| Chip lithography | 7 nm | CCD = 5 nm, I/O = 6 nm |
| Die size | no data | 2x 71 mm2 |
| Maximum core temperature | no data | 100 °C |
| Number of transistors | no data | 13,140 million |
| 64 bit support | + | + |
| Windows 11 compatibility | - | + |
| Unlocked multiplier | Yes | Yes |
Compatibility
Information on Ryzen 9 3900 and Ryzen 9 7945HX 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 | no data | 1 |
| Socket | AM4 (1331) | FL1 |
| Power consumption (TDP) | 65 Watt | 55 Watt |
Technologies and extensions
Technological solutions and additional instructions supported by Ryzen 9 3900 and Ryzen 9 7945HX. 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 | DDR5-5200 RAM, PCIe 5, MMX, SSE, SSE2, SSE3, SSSE3, SSE4A, SSE4.1, SSE4.2, AVX, AVX2, AVX-512, BMI2, ABM, FMA, ADX, SMEP, SMAP, SMT, CPB, AES-NI, RDRAND, RDSEED, SHA, SME |
| AES-NI | + | + |
| FMA | no data | + |
| AVX | + | + |
Virtualization technologies
Virtual machine speed-up technologies supported by Ryzen 9 3900 and Ryzen 9 7945HX are enumerated here.
| AMD-V | + | + |
Memory specs
Types, maximum amount and channel quantity of RAM supported by Ryzen 9 3900 and Ryzen 9 7945HX. Depending on the motherboard, higher memory frequencies may be supported.
| Supported memory types | DDR4-3200 | DDR5 |
| Maximum memory size | 128 GB | no data |
| Max memory channels | 2 | no data |
| Maximum memory bandwidth | 51.196 GB/s | no data |
| ECC memory support | - | no data |
Graphics specifications
General parameters of integrated GPUs, if any.
| Integrated graphics card | - | AMD Radeon 610M |
Peripherals
Specifications and connection of peripherals supported by Ryzen 9 3900 and Ryzen 9 7945HX.
| PCIe version | no data | 5.0 |
| PCI Express lanes | no data | 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.
Ryzen 9 7945HX outperforms Ryzen 9 3900 by 78% based on our aggregated benchmark results.
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.
Benchmark coverage: 68%
Ryzen 9 7945HX outperforms Ryzen 9 3900 by 78% in Passmark.
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.
Benchmark coverage: 42%
Ryzen 9 7945HX outperforms Ryzen 9 3900 by 66% in GeekBench 5 Single-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.
Benchmark coverage: 42%
Ryzen 9 7945HX outperforms Ryzen 9 3900 by 67% in GeekBench 5 Multi-Core.
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.
Benchmark coverage: 20%
Ryzen 9 7945HX outperforms Ryzen 9 3900 by 49% in Cinebench 10 32-bit single-core.
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.
Benchmark coverage: 19%
Ryzen 9 7945HX outperforms Ryzen 9 3900 by 62% in Cinebench 10 32-bit multi-core.
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.
Benchmark coverage: 17%
Ryzen 9 7945HX outperforms Ryzen 9 3900 by 108% in Cinebench 11.5 64-bit multi-core.
Cinebench 15 64-bit multi-core
Cinebench Release 15 Multi Core is a variant of Cinebench R15 which uses all the processor threads.
Benchmark coverage: 15%
Ryzen 9 7945HX outperforms Ryzen 9 3900 by 98% in Cinebench 15 64-bit multi-core.
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.
Benchmark coverage: 15%
Ryzen 9 7945HX outperforms Ryzen 9 3900 by 56% in Cinebench 15 64-bit single-core.
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.
Benchmark coverage: 14%
Ryzen 9 7945HX outperforms Ryzen 9 3900 by 64% in Cinebench 11.5 64-bit single-core.
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.
Benchmark coverage: 13%
Ryzen 9 7945HX outperforms Ryzen 9 3900 by 143% in TrueCrypt AES.
Pros & cons summary
| Performance score | 19.92 | 35.52 |
| Recency | 9 October 2019 | 4 January 2023 |
| Physical cores | 12 | 16 |
| Threads | 24 | 32 |
| Power consumption (TDP) | 65 Watt | 55 Watt |
The Ryzen 9 7945HX 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 7945HX is a notebook one.
Should you still have questions on choice between Ryzen 9 3900 and Ryzen 9 7945HX, ask them in Comments section, and we shall answer.
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