AMD Ryzen 9 9955HX vs AMD Ryzen AI 7 345 Comparison

Head-to-Head Benchmarks

The benchmark data shows a decisive sweep: the AMD Ryzen 9 9955HX wins all 15 recorded head-to-head comparisons against the AMD Ryzen AI 7 345. No test in the database favors the Ryzen AI 7 345. The margins, however, vary considerably by workload type, and that variance tells the real story.

The largest single gap appears in PassMark's find prime numbers test. The Ryzen 9 9955HX scores 287, while the Ryzen AI 7 345 scores 62, a delta of 362.9%. This is a heavily parallel integer workload that rewards core count and memory bandwidth, both of which favor the 16-core part. The Cinebench multicore results follow the same pattern. In Cinebench R23 multicore, the 9955HX posts 37159 versus 11461, a 224.2% advantage. The R15 multicore run shows 5905 against 1712, a 244.9% gap. These are the expected results for a 16-core, 32-thread processor facing a 6-core, 12-thread part.

The margin narrows substantially in single-threaded tests. Cinebench R23 singlecore gives the 9955HX 2174 points versus 1818 for the AI 7 345, a 19.6% lead. The R15 singlecore result is 336 versus 271, a 24% difference. PassMark single thread shows 4393 versus 3875, a 13.4% gap. The single-thread gap is still clear, but it is roughly one-fifth the size of the multicore gap. This indicates that both processors use the same Zen 5 core design, and the per-core performance difference comes down to clock speed and power delivery rather than architectural generation.

Intermediate gaps appear in the PassMark math suite. Floating point math shows 136682 versus 42621, a 220.7% delta. Integer math shows 212598 versus 63475, a 234.9% delta. Extended instructions show 57946 versus 17003, a 240.8% delta. Data compression shows 731998 versus 237484, a 208.2% delta. Data encryption shows 37330 versus 11814, a 216% delta. Random string sorting shows 77890 versus 25435, a 206.2% delta. All of these scale strongly with core count, and the 9955HX doubles the core count of its rival and then some.

The PassMark multithread score lands at 56171 versus 19927, a 181.9% delta. The physics test, which is another multithreaded workload, shows 2720 versus 1089, a 149.8% delta. These are the smallest of the multithreaded deltas, but they still represent massive advantages. The pattern across all tests is consistent: the 9955HX leads in every category, with single-thread leads of roughly 13-24% and multithreaded leads of roughly 150-363%.

Architecture Differences

The two processors share the same manufacturing foundation but differ sharply in configuration. Both are built on TSMC's 4 nm process node. Both use the Zen 5 architecture, though the Ryzen AI 7 345 uses a hybrid arrangement described in the database as Zen 5 / Zen 5c, while the Ryzen 9 9955HX uses straight Zen 5. The 9955HX belongs to the 9000 series with the codename Fire Range. The AI 7 345 belongs to the Ryzen AI 300 series with the codename Krackan Point.

Core counts are the primary differentiator. The 9955HX has 16 cores and 32 threads. The AI 7 345 has 6 cores and 12 threads. Base clocks are 2.50 GHz for the 9955HX and 2.00 GHz for the AI 7 345. Boost clocks are 5.40 GHz and 4.60 GHz respectively. The 9955HX runs at a 55 W TDP, while the AI 7 345 runs at 28 W. The 9955HX has an unlocked multiplier; the AI 7 345 does not.

Cache allocation is another major split. Both use 80 KB of L1 per core and 1 MB of L2 per core. The L3 cache, however, is dramatically different. The 9955HX has 64 MB of shared L3. The AI 7 345 has only 4 MB of L3. This 16x difference in L3 capacity is a key reason the 9955HX dominates cache-sensitive workloads like data compression and integer math.

The memory controllers are similar in bandwidth. Both support dual-channel memory at 89.6 GB/s. The 9955HX supports DDR5. The AI 7 345 supports both DDR5 and LPDDR5X. The 9955HX supports ECC memory; the AI 7 345 does not. The 9955HX uses PCIe Gen 5 with 28 CPU lanes. The AI 7 345 uses PCIe Gen 4 with 14 CPU lanes. The 9955HX uses AMD Socket FL1; the AI 7 345 uses AMD Socket FP8. The integrated graphics differ as well: the 9955HX carries a Radeon 610M, while the AI 7 345 carries a Radeon 840M.

The 9955HX is listed with 16,630 million transistors across a die size of 2x 70.6 mm². The AI 7 345 has no transistor or die size figures recorded in the database. Release dates are nine days apart: the 9955HX on 2025-01-05 and the AI 7 345 on 2025-01-14.

Where Each One Wins

The recorded data leaves no ambiguity about which processor wins individual tests. The Ryzen 9 9955HX wins every benchmark in the head-to-head set. The question is not whether the AI 7 345 can beat it in any workload, because the data says it cannot. The question is how large the gap is and what that means for different usage patterns.

For heavily multithreaded workloads, the 9955HX is in another class. The 362.9% lead in prime number finding, the 244.9% lead in Cinebench R15 multicore, and the 224.2% lead in Cinebench R23 multicore all point to a processor built for sustained parallel throughput. Rendering, video encoding, software compilation, scientific simulation, and batch data processing would all favor the 9955HX by margins in the 150-360% range based on the math and compression results.

For lightly threaded workloads, the 9955HX still wins but by a much smaller margin. The 13.4% lead in PassMark single thread and the 19.6% lead in Cinebench R23 singlecore suggest that everyday desktop responsiveness, office productivity, and lightly threaded applications see a modest but real advantage. The higher boost clock of 5.40 GHz versus 4.60 GHz explains part of this, and the larger L3 cache likely contributes to the rest.

The AI 7 345 has no benchmark wins in the database. Its value proposition lies elsewhere. It draws less power at 28 W versus 55 W, which matters for thin-and-light laptops and battery life. It also includes a Radeon 840M integrated GPU, a more capable iGPU than the Radeon 610M in the 9955HX, though the database does not include graphics benchmarks for either processor. Its smaller size and lower core count make it suitable for compact systems where thermals and power budgets are constrained. The data does not show it winning any CPU benchmark, but it does show it existing in a lower power class.

The Verdict

The recorded benchmarks are unambiguous. The AMD Ryzen 9 9955HX outperforms the AMD Ryzen AI 7 345 in every measured test. The average benchmark score for the 9955HX is 91199, placing it in the 96th percentile of all CPUs in the database. The AI 7 345 averages 29461, placing it in the 81st percentile. The 9955HX sits in the company of the Intel Xeon 654, which scores 90717 with a 0.5% delta, and the AMD Ryzen AI Max+ 392, which scores 90541 with a 0.7% delta. The AI 7 345, by contrast, matches the AMD Ryzen 7 3800X at a 0% delta and runs close to the Intel Core i5-13500HX at a 0.7% delta.

For a user who needs maximum CPU throughput in a mobile platform, the 9955HX is the clear choice. Its 16 cores, 32 threads, 64 MB of L3, and 5.40 GHz boost clock deliver multicore performance that is more than double the AI 7 345 in most workloads. It also leads in single-thread performance by 13-24%, so there is no workload category where the AI 7 345 is faster.

For a user who prioritizes power efficiency, compact system design, or integrated graphics capability, the AI 7 345 has a role. It operates at 28 W versus 55 W, uses the same 4 nm process, and includes a more advanced Radeon 840M iGPU. It supports LPDDR5X memory, which is common in thin laptops. But the CPU performance data shows a large gap in every direction. The choice, strictly from the data, is between maximum performance and lower power consumption. There is no performance argument for the AI 7 345.

FAQ

Q: Which processor wins more benchmarks in the head-to-head comparison?

A: The AMD Ryzen 9 9955HX wins all 15 recorded head-to-head benchmarks. The AMD Ryzen AI 7 345 wins none.

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

A: The 9955HX leads by 13.4% in PassMark single thread, 19.6% in Cinebench R23 singlecore, and 24% in Cinebench R15 singlecore.

Q: How large is the multicore performance gap?

A: The 9955HX leads by 224.2% in Cinebench R23 multicore, 244.9% in Cinebench R15 multicore, and 181.9% in PassMark multithread.

Q: What is the biggest benchmark margin between the two?

A: The largest margin is in PassMark find prime numbers, where the 9955HX scores 287 versus 62, a delta of 362.9%.

Q: Do both processors use the same manufacturing process?

A: Yes, both are built on TSMC's 4 nm process node. Both also use the Zen 5 architecture, though the AI 7 345 uses a Zen 5 / Zen 5c hybrid arrangement.

Q: What are the core and thread counts for each?

A: The 9955HX has 16 cores and 32 threads. The AI 7 345 has 6 cores and 12 threads.

Specification Differences

| Field | AMD Ryzen 9 9955HX | AMD Ryzen AI 7 345 |

|---|---|---|

| Cores | 16 | 6 |

| Threads | 32 | 12 |

| Base clock | 2.50 GHz | 2.00 GHz |

| Boost clock | 5.40 GHz | 4.60 GHz |

| TDP | 55 W | 28 W |

| Socket | AMD Socket FL1 | AMD Socket FP8 |

| Codename | Fire Range | Krackan Point |

| Generation | Ryzen 9 (Zen 5, Fire Range) | Ryzen AI 300 (Zen 5 / Zen 5c) |

| Process node | 4 nm (TSMC) | 4 nm (TSMC) |

| Transistors | 16,630 million | Not recorded |

| Die size | 2x 70.6 mm² | Not recorded |

| L3 cache | 64 MB (shared) | 4 MB |

| Memory support | DDR5 | DDR5, LPDDR5X |

| ECC memory | Yes | No |

| PCIe | Gen 5, 28 lanes | Gen 4, 14 lanes |

| Integrated graphics | Radeon 610M | Radeon 840M |

| Multiplier unlocked | Yes | No |

| Part number | 100-000001028 | 100-000002122 |

| Release date | 2025-01-05 | 2025-01-14 |

| Avg benchmark score | 91199 | 29461 |

| Percentile vs all CPUs | 96 | 81 |