AMD Ryzen 3 3100U vs AMD Ryzen 5 8400F Comparison

AMD Ryzen 3 3100U and AMD Ryzen 5 8400F occupy different tiers in the benchmark database, with the 8400F delivering a dominant performance profile across every recorded workload. The 3100U is a mobile-oriented 2-core processor from the 3000 series, while the 8400F is a desktop 6-core part from the 8000 series. The recorded data shows a complete sweep for the 8400F in head-to-head tests, with the largest gaps appearing in multi-threaded and instruction-heavy tasks. The 8400F also holds a higher percentile ranking among all CPUs, placing at the 77th percentile compared to the 3100U's 62nd percentile, and its average benchmark score of 25,005 dwarfs the 3100U's 6,247.

Head-to-Head Benchmarks

The head-to-head results are unambiguous: the AMD Ryzen 5 8400F wins all 11 recorded benchmark comparisons. The most lopsided victory comes in extended instructions, where the 8400F scores 22,175 against the 3100U's 2,116, a delta of 90.5% in favor of the newer part. This indicates a massive advantage in workloads that leverage advanced instruction sets, a direct consequence of the architectural generation gap between Zen 4 and Zen+.

Data encryption shows a similar pattern, with the 8400F scoring 16,646 versus 1,972 for the 3100U, an 88.2% gap. Integer math follows closely: the 8400F delivers 74,021 points compared to 8,873, a difference of 88%. Floating-point math also favors the 8400F heavily, with 46,217 points against 5,854, an 87.3% delta. These results confirm that the 8400F is not merely faster, but categorically more capable in compute-intensive tasks.

The multithreaded PassMark score shows an 86.3% gap, with the 8400F at 24,389 and the 3100U at 3,348. This aligns with the core and thread counts: the 8400F has 6 cores and 12 threads, while the 3100U has just 2 cores and 2 threads. The data compression test also reflects this disparity, with the 8400F scoring 288,158 against 38,455, an 86.7% delta. Random string sorting, another parallel workload, shows the 8400F at 34,604 versus 4,666, an 86.5% gap.

Even in single-threaded tests, where the 3100U's lower core count is less of a disadvantage, the 8400F leads substantially. The PassMark single-thread score for the 8400F is 3,685, while the 3100U manages 1,592, a 56.8% delta. This is a smaller gap than the multi-threaded results, but it still shows a clear generational advantage in per-core performance. The physics test, which often scales with both clock speed and core count, shows the 8400F at 1,332 versus 232, an 82.6% delta. Prime number finding also favors the 8400F, with 89 points against 18, a 79.8% gap.

Where Each One Wins

The data does not provide any workload where the AMD Ryzen 3 3100U outperforms the AMD Ryzen 5 8400F. Every recorded benchmark, from data compression to floating-point math, shows the 8400F ahead. The 3100U's only advantage lies in its physical characteristics: it is a mobile processor with a 15-watt TDP, making it suitable for power-constrained systems, whereas the 8400F is a desktop part with a 65-watt TDP. The 3100U also includes integrated Radeon Vega 8 graphics, a feature absent from the 8400F, which has no integrated graphics.

For users prioritizing raw compute throughput, the 8400F is the clear choice based on the recorded scores. Its 6-core, 12-thread configuration delivers a multithreaded score of 24,389, which is roughly 7 times higher than the 3100U's 3,348. The 8400F also excels in memory bandwidth, with 83.2 GB/s supported versus 38.4 GB/s for the 3100U, which benefits memory-sensitive workloads. The 3100U's integrated graphics make it a viable option for systems requiring a display output without a discrete GPU, but this comes at the cost of CPU performance.

The 8400F's nearest rivals in the database include the AMD Ryzen 5 7500F, which scores 24,964 with a 0.2% delta, and the Intel Core i7-11850H at 24,935 with a 0.3% delta. These results place the 8400F in a competitive position among recent mid-range desktop processors. The 3100U's nearest rivals include the AMD Ryzen Threadripper 1950X at 6,231 with a 0.3% delta and the Intel Core i9-10920X at 6,347 with a 1.6% delta, indicating that the 3100U's average score is comparable to much older high-end parts, but it does not approach the 8400F's performance tier.

FAQ

Q: Which processor has a higher average benchmark score?

A: The AMD Ryzen 5 8400F has an average benchmark score of 25,005, while the AMD Ryzen 3 3100U scores 6,247. The 8400F also ranks at the 77th percentile of all CPUs, compared to the 3100U's 62nd percentile.

Q: How large is the single-thread performance gap?

A: In the PassMark single-thread test, the 8400F scores 3,685 versus the 3100U's 1,592, a delta of 56.8% in favor of the 8400F. This indicates a significant per-core advantage for the newer architecture.

Q: Does the 3100U have any integrated graphics?

A: Yes, the AMD Ryzen 3 3100U includes Radeon Vega 8 integrated graphics. The AMD Ryzen 5 8400F has no integrated graphics, so it requires a discrete GPU for display output.

Q: What is the TDP difference between the two processors?

A: The 3100U has a TDP of 15 watts, while the 8400F has a TDP of 65 watts. This makes the 3100U more suitable for low-power mobile systems, though it comes with a substantial performance penalty.

Q: Which processor supports faster memory?

A: The 8400F supports DDR5 memory with a bandwidth of 83.2 GB/s, while the 3100U supports DDR4 with a bandwidth of 38.4 GB/s. The 8400F's memory subsystem offers a 44.8 GB/s advantage in theoretical bandwidth.

Q: How many cores and threads does each processor have?

A: The 3100U has 2 cores and 2 threads. The 8400F has 6 cores and 12 threads, which explains its dominant performance in multi-threaded benchmarks.

Specification Differences

The two processors differ in nearly every core specification. The 3100U has 2 cores and 2 threads, while the 8400F has 6 cores and 12 threads. Base clocks differ substantially: the 3100U runs at 1.90 GHz, and the 8400F at 4.20 GHz. Boost clocks follow the same pattern, with the 3100U reaching 3.20 GHz and the 8400F boosting to 4.70 GHz. The 3100U has a TDP of 15 watts, whereas the 8400F has a TDP of 65 watts.

The cache hierarchies are also distinct. The 3100U provides 96 KB of L1 cache per core, 512 KB of L2 per core, and 4 MB of shared L3 cache. The 8400F offers 64 KB of L1 per core, 1 MB of L2 per core, and 16 MB of shared L3 cache. This gives the 8400F a larger total cache, particularly in L3, which is 12 MB larger than the 3100U's L3.

Memory support differs by generation: the 3100U uses DDR4, while the 8400F uses DDR5. The memory bus is dual-channel for both, but the bandwidth is far higher on the 8400F at 83.2 GB/s versus 38.4 GB/s. The PCIe interface also differs, with the 3100U supporting Gen 3 and the 8400F supporting Gen 4 with 20 lanes (CPU only). The 3100U includes integrated Radeon Vega 8 graphics, while the 8400F has no integrated graphics. The 8400F has an unlocked multiplier, while the 3100U does not. The 8400F's launch MSRP is $170, and it was released in 2024, while the 3100U's release date is listed as 2026.

Architecture Differences

The architectural gap between the two processors is significant. The 3100U is based on the Picasso codename, which uses the Zen+ architecture on a 12 nm process from GlobalFoundries. It has 4,940 million transistors on a 210 mm² die. The 8400F uses the Phoenix codename with the Zen 4 architecture on a 4 nm process from TSMC. It has 25,000 million transistors on a 178 mm² die. This means the 8400F packs over 5 times more transistors into a smaller die, reflecting the density improvements of the newer process node.

The 8400F's Zen 4 architecture delivers a substantial instruction-per-clock improvement over Zen+, which is evident in the single-thread benchmark gap. The 8400F also has a larger L3 cache at 16 MB shared, compared to 4 MB shared on the 3100U. The 8400F's 1 MB L2 per core is double the 3100U's 512 KB per core. These cache differences contribute to the 8400F's lead in data compression and encryption tests, where larger caches reduce memory latency overhead.

The 8400F supports PCIe Gen 4, which offers double the bandwidth of the 3100U's Gen 3 support. The 8400F also uses DDR5 memory, which is a generational upgrade over the 3100U's DDR4 support. The 8400F's memory bandwidth of 83.2 GB/s is more than double the 3100U's 38.4 GB/s. The 8400F is a desktop processor with a 65-watt TDP, while the 3100U is a mobile processor with a 15-watt TDP, reflecting their different market segments. The 8400F has no integrated graphics, while the 3100U includes Radeon Vega 8, which adds display output capability without a discrete GPU.

The Verdict

The benchmark data makes the performance hierarchy clear. The AMD Ryzen 5 8400F is superior to the AMD Ryzen 3 3100U in every recorded test, with deltas ranging from 56.8% in single-threaded work to 90.5% in extended instructions. The 8400F's 6 cores and 12 threads, combined with its higher clocks and Zen 4 architecture, deliver a multithreaded score of 24,389, which is 7.3 times the 3100U's 3,348. Its average benchmark score of 25,005 places it at the 77th percentile of all CPUs, while the 3100U sits at the 62nd percentile with an average of 6,247.

The 3100U remains a functional choice for mobile systems requiring low power consumption, as its 15-watt TDP and integrated graphics reduce system complexity. However, the data shows no performance scenario where the 3100U competes with the 8400F. The 8400F's nearest rivals, including the AMD Ryzen 5 7500F and Intel Core i7-11850H, have average scores within 0.4% of its own, confirming that it sits in a competitive desktop segment. Users building a desktop system with a discrete GPU should select the 8400F, as its DDR5 support, PCIe Gen 4, and higher core count provide a clearly superior compute profile. Users constrained to low-power mobile platforms should expect the 3100U to handle basic tasks, but the recorded benchmarks indicate a massive performance deficit relative to the 8400F.