AMD Ryzen 9 9955HX vs Intel Core Ultra 7 366H Comparison

Head-to-Head Benchmarks

The recorded benchmark data shows a clear split between the AMD Ryzen 9 9955HX and the Intel Core Ultra 7 366H. The AMD part wins 11 of the 15 head-to-head comparisons, while the Intel part wins 4. The most dramatic AMD victory comes in Cinebench R15 multi-core, where the Ryzen 9 9955HX scores 5905 against the Intel chip's 2870, a 105.7% advantage. That is more than double the score, and it sets the tone for the multi-threaded workloads.

Cinebench R23 multi-core tells a similar story, though with a smaller gap. The AMD Ryzen 9 9955HX scores 37159, while the Intel Core Ultra 7 366H scores 28477. That is a 30.5% lead for AMD. The PassMark integer math test shows the largest single delta: AMD scores 212598, Intel scores 83695, a 154% difference. Data compression also heavily favors AMD, with scores of 731998 versus 327455, a 123.5% margin. Extended instructions follow at 115.4% in AMD's favor, and random string sorting is 95.6% ahead for AMD.

The Intel Core Ultra 7 366H does win in specific single-threaded and latency-sensitive tests. In Cinebench R15 single-core, Intel scores 405 against AMD's 336, a 17% lead. In Cinebench R23 single-core, the gap widens: Intel scores 4020, AMD scores 2174, a 45.9% advantage for Intel. That is a substantial difference in a single-core rendering test. The Intel part also wins PassMark find prime numbers (326 versus 287, a 12% lead) and PassMark physics (2880 versus 2720, a 5.6% lead).

However, the PassMark single-thread test goes the other way. AMD scores 4393, Intel scores 4043, an 8.7% advantage for AMD. So the two processors trade blows in single-threaded workloads depending on the test methodology. The Cinebench single-core results favor Intel strongly, while the PassMark single-thread result favors AMD by a smaller margin.

The multi-threaded PassMark test shows AMD at 56171 versus Intel's 33429, a 68% lead. Floating point math also favors AMD, with scores of 136682 versus 103615, a 31.9% margin. Data encryption is 44.4% ahead for AMD (37330 versus 25845). Across the board, the AMD Ryzen 9 9955HX delivers consistently higher throughput in parallel workloads, while the Intel Core Ultra 7 366H shows competitive or superior results in specific single-core tests.

Architecture Differences

The AMD Ryzen 9 9955HX uses the Zen 5 architecture on the Fire Range codename, built on a 4 nm process at TSMC. It has 16 cores and 32 threads, with a base clock of 2.50 GHz and a boost clock of 5.40 GHz. The Intel Core Ultra 7 366H uses the Panther Lake architecture, built on a 3 nm process at Intel. It also has 16 cores but only 16 threads, with a base clock of 2.00 GHz and a boost clock of 4.80 GHz. The thread count difference is the most significant architectural split: AMD offers simultaneous multithreading, Intel does not on this part.

Cache configurations differ substantially. The AMD chip has 80 KB of L1 per core, 1 MB of L2 per core, and 64 MB of shared L3. The Intel chip has 192 KB of L1 per core, 2.5 MB of L2 per core, but only 18 MB of shared L3. The AMD L3 cache is more than three times larger, which helps with repeated data access in heavy workloads. The Intel chip has larger per-core L1 and L2 caches, which likely contributes to its strong single-core results in the Cinebench tests.

Memory support also differs. Both support DDR5, but the Intel part adds LPDDR5X. The AMD chip has a dual-channel memory bus with 89.6 GB/s bandwidth, while the Intel chip has a dual-channel bus with 115.2 GB/s bandwidth. That is a 28.6% higher memory bandwidth figure for Intel, which may help in memory-bound tasks. AMD supports ECC memory, Intel does not. PCIe lanes differ: AMD provides Gen 5 with 28 lanes (CPU only), Intel provides Gen 5 with 12 lanes (CPU only).

The integrated graphics are different as well. AMD uses the Radeon 610M, Intel uses Intel Xe3 Graphics. The AMD part has an unlocked multiplier, while the Intel part is locked. The AMD processor uses an AMD Socket FL1, while the Intel part uses Intel BGA 2540. Both are active production parts for the mobile market segment. The AMD Ryzen 9 9955HX has a TDP of 55, the Intel Core Ultra 7 366H has a TDP of 25. That power envelope difference explains some of the performance gap, but the architectural choices also play a role.

The Verdict

The benchmark data indicates that the AMD Ryzen 9 9955HX is the stronger processor for multi-threaded and throughput-oriented tasks. It wins 11 of 15 head-to-head comparisons, with leads ranging from 8.7% in PassMark single-thread to 154% in integer math. The Cinebench R23 multi-core score of 37159 places it well ahead of the Intel chip's 28477, a 30.5% margin. For rendering, data compression, encryption, and any workload that scales with cores and threads, the AMD part is the clear choice.

The Intel Core Ultra 7 366H wins 4 tests, all of which are single-core or low-thread-count workloads. Its Cinebench R23 single-core score of 4020 is 45.9% higher than AMD's 2174, which is a decisive advantage in lightly threaded rendering tasks. It also wins Cinebench R15 single-core, PassMark find prime numbers, and PassMark physics. The 25 TDP makes it a more power-efficient option on paper, but the database does not include battery life or thermal measurements.

The average benchmark score tells the broader story. The AMD Ryzen 9 9955HX has an average score of 91199, while the Intel Core Ultra 7 366H has an average score of 41263. The AMD part sits in the 96th percentile of all CPUs, the Intel part in the 87th percentile. The AMD chip's nearest rivals include the Intel Xeon 654 (0.5% ahead), the AMD Ryzen AI Max+ 392 (0.7% ahead), and the Intel Core Ultra 7 270K Plus (2.8% behind). The Intel part's nearest rivals are clustered much closer: the Intel Core Ultra 7 356H (0.1% behind), the AMD Ryzen AI 5 PRO 440 (0.1% behind), and the AMD Ryzen 9 5900X (0.3% ahead). The Intel part is competitive within its own tier, but the AMD part operates in a higher performance class.

FAQ

Q: Which processor has more threads?

A: The AMD Ryzen 9 9955HX has 32 threads, while the Intel Core Ultra 7 366H has 16 threads. Both have 16 cores, but only the AMD part supports simultaneous multithreading.

Q: How do the single-core scores compare?

A: The Intel Core Ultra 7 366H wins Cinebench R15 single-core (405 versus 336, a 17% lead) and Cinebench R23 single-core (4020 versus 2174, a 45.9% lead). However, the AMD Ryzen 9 9955HX wins PassMark single-thread (4393 versus 4043, an 8.7% lead).

Q: What is the largest performance gap between the two?

A: The largest gap is in PassMark integer math, where the AMD Ryzen 9 9955HX scores 212598 versus the Intel Core Ultra 7 366H's 83695, a 154% difference.

Q: Does the Intel chip have a higher memory bandwidth?

A: Yes. The Intel Core Ultra 7 366H supports 115.2 GB/s memory bandwidth, while the AMD Ryzen 9 9955HX supports 89.6 GB/s. Both use dual-channel memory buses.

Q: Which processor has a larger L3 cache?

A: The AMD Ryzen 9 9955HX has 64 MB of shared L3 cache. The Intel Core Ultra 7 366H has 18 MB of shared L3 cache.

Q: Are both processors unlocked for overclocking?

A: No. The AMD Ryzen 9 9955HX has an unlocked multiplier. The Intel Core Ultra 7 366H does not have an unlocked multiplier.

Where Each One Wins

The AMD Ryzen 9 9955HX wins in every multi-core rendering test, every PassMark math test except find prime numbers, and all data-intensive workloads. The data shows a 105.7% lead in Cinebench R15 multi-core, a 30.5% lead in Cinebench R23 multi-core, and a 68% lead in PassMark multithread. For integer math, data compression, encryption, extended instructions, floating point math, and random string sorting, the AMD chip is significantly ahead. These are the workloads that benefit from 32 threads and 64 MB of L3 cache.

The Intel Core Ultra 7 366H wins in Cinebench R15 single-core, Cinebench R23 single-core, PassMark find prime numbers, and PassMark physics. The Cinebench single-core wins are large: 17% in R15 and 45.9% in R23. The find prime numbers win is 12%, and the physics win is 5.6%. These tests suggest that for short, single-threaded bursts or latency-sensitive operations, the Intel chip has an edge. The higher per-core L1 and L2 caches likely contribute to this behavior.

The PassMark single-thread test is a split result, with AMD winning by 8.7%. So the Intel chip's single-core advantage is not universal across all test methods. The average benchmark scores place the AMD chip at 91199 versus 41263 for Intel, a difference of more than a factor of two. The AMD Ryzen 9 9955HX is in the 96th percentile of all CPUs, while the Intel Core Ultra 7 366H is in the 87th percentile.

Specification Differences

| Specification | AMD Ryzen 9 9955HX | Intel Core Ultra 7 366H |

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

| Cores | 16 | 16 |

| Threads | 32 | 16 |

| Base Clock | 2.50 GHz | 2.00 GHz |

| Boost Clock | 5.40 GHz | 4.80 GHz |

| TDP | 55 | 25 |

| Process Node | 4 nm | 3 nm |

| Foundry | TSMC | Intel |

| Architecture | Zen 5 | Panther Lake |

| L1 Cache | 80 KB (per core) | 192 KB (per core) |

| L2 Cache | 1 MB (per core) | 2.5 MB (per core) |

| L3 Cache | 64 MB (shared) | 18 MB (shared) |

| Memory Support | DDR5 | DDR5, LPDDR5X |

| Memory Bandwidth | 89.6 GB/s | 115.2 GB/s |

| ECC Memory | Yes | No |

| PCIe | Gen 5, 28 Lanes (CPU only) | Gen 5, 12 Lanes (CPU only) |

| Integrated Graphics | Radeon 610M | Intel Xe3 Graphics |

| Socket | AMD Socket FL1 | Intel BGA 2540 |

| Multiplier Unlocked | Yes | No |

| Release Date | 2025-01-05 | 2026-01-04 |