AMD Ryzen 9 7945HX vs AMD Ryzen Threadripper PRO 3955WX Comparison

The benchmark data presents a clear and unequivocal picture: the AMD Ryzen 9 7945HX, a mobile processor, outperforms the desktop-class AMD Ryzen Threadripper PRO 3955WX in every single measured test. The Ryzen 9 7945HX secures 19 wins out of 19 head-to-head benchmarks, leaving the Threadripper PRO with zero wins. This is a sweeping victory that underscores a significant generational leap in CPU architecture and efficiency, even when comparing a laptop part to a workstation desktop part.

Head-to-Head Benchmarks

The most dramatic differences appear in single-threaded performance, where the Ryzen 9 7945HX’s modern architecture delivers crushing blows. In Geekbench single-core, the 7945HX scores 2769 against the 3955WX’s 1684, a massive 64.4% advantage. Similarly, in PassMark's single-thread test, the 7945HX posts 4040 versus 2679, a 50.8% lead. Cinebench R23 single-core results reinforce this trend, with the 7945HX scoring 6547 compared to 4818 for the Threadripper, a 35.9% delta. These results indicate that for everyday responsiveness, lightly-threaded applications, and gaming, the Ryzen 9 7945HX is in a different league entirely.

The multi-core results, while narrower, still heavily favor the Ryzen 9 7945HX. In Cinebench R23 multi-core, the 7945HX scores 46375 versus 34131 for the 3955WX, a 35.9% advantage. This consistency of a 35.9% delta across all Cinebench R15, R20, and R23 tests (both single and multi-core) is remarkable. The Geekbench multi-core test shows a 29% lead for the 7945HX (16156 vs 12523). PassMark’s multithread score has the 7945HX ahead by 35.8% (54548 vs 40155). These results prove that despite being a mobile chip with a 55W TDP, the 7945HX’s 16 cores and 32 threads are more efficient and powerful than the Threadripper’s 16 cores and 32 threads.

Looking at specific computational workloads, the Ryzen 9 7945HX shows its strengths in floating-point and integer math. In PassMark floating-point math, it scores 123390, which is 58.2% higher than the 3955WX’s 77979. The integer math test shows a 56.7% lead (207524 vs 132456). Even in the find prime numbers test, a classic multi-core workload, the 7945HX wins by 43.4% (284 vs 198). The smallest margin of victory is in PassMark physics, where the 7945HX scores 2500 versus 2460, a narrow 1.6% lead. This indicates that in this specific test, the two processors are nearly on par, but it is the only benchmark where the Threadripper PRO comes close.

The Verdict

From the data, the choice is straightforward. The AMD Ryzen 9 7945HX is the superior processor for almost every conceivable workload. Its wins are not marginal; they are substantial, ranging from a 1.6% lead in PassMark physics to a 64.4% lead in Geekbench single-core. The Ryzen 9 7945HX should be the pick for anyone prioritizing raw performance, whether for gaming, content creation, or professional applications that rely on both single-threaded speed and multi-threaded throughput.

The AMD Ryzen Threadripper PRO 3955WX, despite its workstation pedigree and higher 280W TDP, cannot compete with the newer Zen 4 architecture of the 7945HX. Its only potential advantage lies outside the scope of the benchmark scores, in its platform features like an eight-channel memory bus and 128 PCIe Gen 4 lanes. However, based strictly on the performance data available, the 7945HX is the definitive winner. The Threadripper PRO would only be considered for a build requiring those specific platform capabilities, not for its raw compute performance, which is consistently and significantly lower.

Architecture Differences

The two processors are built on fundamentally different architectures from different generations. The AMD Ryzen 9 7945HX is based on the Zen 4 architecture, codenamed Dragon Range, and is manufactured on a 5 nm process by TSMC. In contrast, the AMD Ryzen Threadripper PRO 3955WX uses the older Zen 2 architecture, codenamed Castle Peak, and is built on a 7 nm process. This generational gap explains the massive performance differences, as Zen 4 delivers substantially higher instructions per clock (IPC) and better power efficiency.

The transistor counts and die sizes also reflect the architectural divide. The 7945HX packs 13,140 million transistors across a die size of 2x 71 mm², while the 3955WX contains 7,600 million transistors on a 2x 74 mm² die. This shows that the Zen 4 chip crams nearly twice as many transistors into a slightly smaller area, contributing to its higher performance. The cache configurations differ as well, with the 7945HX featuring 1 MB of L2 cache per core, whereas the 3955WX has 512 KB per core. Both share 64 MB of L3 cache, but the newer chip's larger L2 cache helps reduce latency and improve performance.

Another key architectural difference is the memory support. The Ryzen 9 7945HX supports DDR5 memory with a dual-channel memory bus and a bandwidth of 83.2 GB/s. The Threadripper PRO 3955WX supports DDR4 memory but with an eight-channel memory bus, giving it a much higher bandwidth of 204.8 GB/s. While the Threadripper has a bandwidth advantage, the 7945HX’s faster DDR5 memory and lower latency help it win in the benchmarks. The 7945HX also includes integrated Radeon 610M graphics, while the 3955WX has no integrated graphics at all. Finally, the 7945HX features a PCIe Gen 5 interface with 28 lanes, while the 3955WX offers PCIe Gen 4 with a massive 128 lanes.

Specification Differences

The specification sheets highlight the different design goals of these two processors. The most obvious difference is the TDP: the Ryzen 9 7945HX has a 55W TDP, while the Threadripper PRO 3955WX has a 280W TDP. Despite the Threadripper drawing over five times the power, it still loses in every benchmark, showcasing the 7945HX’s incredible efficiency. Clock speeds also differ, with the 7945HX having a base clock of 2.50 GHz and a boost clock of 5.40 GHz, while the 3955WX has a higher base clock of 3.90 GHz but a significantly lower boost clock of 4.30 GHz.

The sockets and market segments are completely different. The 7945HX uses AMD Socket FL1 and is a mobile processor, released on 2023-01-03. The 3955WX uses AMD Socket WRX8 and is a desktop processor, released earlier on 2020-07-13. The 7945HX has an unlocked multiplier, allowing for overclocking, while the 3955WX does not. The memory support is split between DDR5 for the mobile chip and DDR4 for the desktop chip. The PCIe capabilities are also a major divider: the 7945HX offers Gen 5 with 28 lanes, while the 3955WX offers Gen 4 with 128 lanes. Both support ECC memory. The launch MSRP for the Threadripper PRO 3955WX was $1149; the 7945HX has no listed launch MSRP in the data.

FAQ

Q: Which processor is faster in single-threaded tasks?

A: The AMD Ryzen 9 7945HX is significantly faster. It leads by 64.4% in Geekbench single-core (2769 vs 1684) and by 50.8% in PassMark single-thread (4040 vs 2679).

Q: How do the two chips compare in multi-core performance?

A: The Ryzen 9 7945HX wins all multi-core tests. It leads by 35.9% in Cinebench R23 multi-core (46375 vs 34131) and by 35.8% in PassMark multithread (54548 vs 40155).

Q: Does the Threadripper PRO 3955WX win any benchmark?

A: No. Out of the 19 head-to-head benchmarks, the Ryzen 9 7945HX wins all of them. The Threadripper PRO 3955WX has zero wins.

Q: What is the difference in memory bandwidth between the two?

A: The Threadripper PRO 3955WX has a much higher memory bandwidth of 204.8 GB/s due to its eight-channel DDR4 memory bus. The Ryzen 9 7945HX has a bandwidth of 83.2 GB/s from its dual-channel DDR5 bus.

Q: Which processor has more PCIe lanes?

A: The Threadripper PRO 3955WX has far more, offering 128 PCIe Gen 4 lanes. The Ryzen 9 7945HX has 28 PCIe Gen 5 lanes.

Q: Are both processors based on the same architecture?

A: No. The Ryzen 9 7945HX uses the newer Zen 4 architecture (5 nm process), while the Threadripper PRO 3955WX uses the older Zen 2 architecture (7 nm process).

Where Each One Wins

The benchmark data is unambiguous: the AMD Ryzen 9 7945HX wins in every single performance category measured, making it the clear choice for nearly all use cases. Its victory in single-threaded tests (64.4% in Geekbench) makes it the better option for gaming, web browsing, and any application that relies heavily on a single core. Its dominance in multi-threaded tests (35.9% in Cinebench R23) makes it superior for video editing, 3D rendering, software compilation, and other heavily parallel workloads. The 7945HX is also the more efficient part, delivering all this performance within a 55W TDP, making it suitable for high-performance laptops.

The only area where the AMD Ryzen Threadripper PRO 3955WX could be considered a "winner" is in platform features, not raw performance. Its eight-channel memory bus provides 204.8 GB/s of bandwidth, which is 2.5 times higher than the 7945HX’s 83.2 GB/s. For workloads that are extremely sensitive to memory bandwidth, such as large-scale data analysis or certain scientific simulations, this could be an advantage. Additionally, its 128 PCIe Gen 4 lanes are far more numerous than the 28 Gen 5 lanes on the 7945HX, allowing for many more expansion cards, GPUs, and NVMe drives. However, in terms of compute performance as measured by the provided benchmarks, the Ryzen 9 7945HX is the definitive and overwhelming winner.