AMD Ryzen 9 9955HX vs AMD Ryzen AI 5 PRO 440 Comparison

The Verdict

The benchmark data delivers a decisive outcome: the AMD Ryzen 9 9955HX wins every single head-to-head comparison against the AMD Ryzen AI 5 PRO 440. Across 11 recorded benchmark tests, the Ryzen 9 9955HX takes 11 wins, while the Ryzen AI 5 PRO 440 records zero. The average benchmark score tells the same story: the Ryzen 9 9955HX sits at 91,199, placing it in the 96th percentile of all CPUs, while the Ryzen AI 5 PRO 440 averages 41,208, good for the 87th percentile. The gap is not marginal; it is a fundamental performance tier difference.

The Ryzen 9 9955HX is the choice for anyone whose workload scales with core count and raw compute throughput. Its 16 cores and 32 threads, combined with a 5.40 GHz boost clock, deliver multi-threaded scores that dwarf the 6-core, 12-thread Ryzen AI 5 PRO 440. In PassMark multithread testing, the Ryzen 9 9955HX scores 56,171 versus 21,054, a 166.8% advantage. That is not a small edge; it is more than double the throughput.

The Ryzen AI 5 PRO 440 is not without a role, but that role is defined by efficiency and integration rather than peak performance. Its 28 W TDP, versus the Ryzen 9 9955HX's 55 W TDP, makes it a better fit for lighter mobile systems where battery life and thermal headroom matter more than raw compute. The single-thread gap is far narrower: the Ryzen 9 9955HX leads by 16.1% in PassMark single-thread testing, 4,393 to 3,785. That means for everyday responsive tasks and lightly threaded applications, the Ryzen AI 5 PRO 440 remains competitive, even though it loses the head-to-head.

The verdict from the data is simple: pick the Ryzen 9 9955HX for maximum performance, particularly in multi-core and compute-heavy scenarios. Pick the Ryzen AI 5 PRO 440 for a lower-power, more integrated mobile platform where the performance deficit is acceptable in exchange for the TDP reduction.

Where Each One Wins

The Ryzen 9 9955HX wins in every measured category, but the magnitude of the win varies dramatically by workload type. The smallest margin is in single-threaded performance, where the Ryzen 9 9955HX scores 4,393 against 3,785, a 16.1% lead. This is the closest contest in the entire dataset. For applications that rely on a single core, the Ryzen AI 5 PRO 440 is within striking distance, and its lower power draw makes it a reasonable alternative.

The largest margins appear in compute-heavy parallel workloads. In PassMark find prime numbers, the Ryzen 9 9955HX scores 287 versus 77, a 272.7% lead. Floating point math shows a 218.4% advantage, with scores of 136,682 versus 42,934. Extended instructions testing delivers a 214% lead, 57,946 versus 18,456. These are workloads that fully utilize all cores and threads, and the 16-core Ryzen 9 9955HX simply overwhelms the 6-core Ryzen AI 5 PRO 440.

Memory and data tasks follow the same pattern. Data compression shows a 185.5% lead, 731,998 versus 256,420. Random string sorting is close behind at 185.8%, 77,890 versus 27,252. Integer math delivers a 222.2% advantage, 212,598 versus 65,991. Data encryption shows a 200.6% lead, 37,330 versus 12,418. Physics simulation, a heavily multi-threaded workload, shows a 143.1% advantage, 2,720 versus 1,119.

The Ryzen AI 5 PRO 440 wins no benchmark categories. Its role is not defined by any single victory but by its overall profile: a 28 W TDP, integrated Radeon 840M graphics, and a dual-channel memory bus that matches the Ryzen 9 9955HX's 89.6 GB/s bandwidth. For users who prioritize lower power consumption and a smaller physical footprint, the Ryzen AI 5 PRO 440 is the sensible pick, not because it wins benchmarks but because it fits a different usage envelope.

Architecture Differences

Both processors are built on AMD's Zen 5 architecture and manufactured by TSMC on a 4 nm process node. That is where the architectural similarities end. The Ryzen 9 9955HX carries the Fire Range codename and belongs to the 9000 series, while the Ryzen AI 5 PRO 440 uses the Gorgon Point codename and is part of the Ryzen AI PRO 400 generation, which combines Zen 5 and Zen 5c cores.

The core configurations diverge sharply. The Ryzen 9 9955HX offers 16 cores and 32 threads, with a base clock of 2.50 GHz and a boost clock of 5.40 GHz. The Ryzen AI 5 PRO 440 offers 6 cores and 12 threads, with a base clock of 2.00 GHz and a boost clock of 4.80 GHz. The Ryzen 9 9955HX also has an unlocked multiplier, allowing overclocking, while the Ryzen AI 5 PRO 440 is locked.

Cache allocation differs significantly. Both processors use 80 KB of L1 cache per core and 1 MB of L2 cache per core. The L3 cache, however, is a major differentiator: the Ryzen 9 9955HX has 64 MB of shared L3 cache, while the Ryzen AI 5 PRO 440 has only 8 MB. This eightfold difference in L3 cache contributes directly to the Ryzen 9 9955HX's dominance in data-heavy workloads like compression and random string sorting.

The physical design also differs. The Ryzen 9 9955HX uses a dual-chiplet design with a die size of 2x 70.6 mm² and 16,630 million transistors. The Ryzen AI 5 PRO 440 uses a monolithic design with a die size of 195 mm². The Ryzen 9 9955HX fits into AMD Socket FL1, while the Ryzen AI 5 PRO 440 uses AMD Socket FP8.

Memory support and I/O show further divergence. Both support dual-channel memory with 89.6 GB/s bandwidth. The Ryzen 9 9955HX supports DDR5, while the Ryzen AI 5 PRO 440 supports both DDR5 and LPDDR5X. Both support ECC memory. The Ryzen 9 9955HX offers PCIe Gen 5 with 28 CPU-only lanes, while the Ryzen AI 5 PRO 440 offers PCIe Gen 4 with 16 CPU-only lanes. Integrated graphics differ as well: the Ryzen 9 9955HX uses a Radeon 610M, while the Ryzen AI 5 PRO 440 uses a Radeon 840M.

FAQ

Q: Which processor is faster in multi-threaded workloads?

A: The AMD Ryzen 9 9955HX is substantially faster. It scores 56,171 in PassMark multithread testing versus 21,054 for the AMD Ryzen AI 5 PRO 440, a 166.8% lead. Its 16 cores and 32 threads give it a decisive advantage over the 6-core, 12-thread Ryzen AI 5 PRO 440.

Q: How close are the two in single-threaded performance?

A: The gap is much smaller. The Ryzen 9 9955HX scores 4,393 in PassMark single-thread testing, while the Ryzen AI 5 PRO 440 scores 3,785, a 16.1% difference. The Ryzen 9 9955HX still wins, but the margin is the narrowest of any benchmark in the comparison.

Q: What is the L3 cache difference between the two?

A: The Ryzen 9 9955HX has 64 MB of shared L3 cache, while the Ryzen AI 5 PRO 440 has 8 MB. Both use 80 KB of L1 cache per core and 1 MB of L2 cache per core.

Q: Which processor has a higher boost clock?

A: The Ryzen 9 9955HX has a boost clock of 5.40 GHz, compared to 4.80 GHz for the Ryzen AI 5 PRO 440. The base clocks are 2.50 GHz and 2.00 GHz, respectively.

Q: Do both processors support ECC memory?

A: Yes, both the Ryzen 9 9955HX and the Ryzen AI 5 PRO 440 support ECC memory. Both also support dual-channel memory with 89.6 GB/s bandwidth.

Q: Which processor has a lower TDP?

A: The Ryzen AI 5 PRO 440 has a TDP of 28 W, while the Ryzen 9 9955HX has a TDP of 55 W. The lower TDP makes the Ryzen AI 5 PRO 440 more suitable for power-constrained mobile designs.

Head-to-Head Benchmarks

The head-to-head data shows a clean sweep for the Ryzen 9 9955HX, but the individual margins reveal where the architecture differences matter most. The largest delta is in PassMark find prime numbers, where the Ryzen 9 9955HX scores 287 against 77, a 272.7% advantage. This test is highly sensitive to core count and integer throughput, and the 16-core processor dominates the 6-core part.

Floating point math shows a 218.4% lead, with the Ryzen 9 9955HX scoring 136,682 versus 42,934. Integer math is nearly identical in scale, a 222.2% advantage, 212,598 versus 65,991. Extended instructions testing delivers a 214% lead, 57,946 versus 18,456. These three tests collectively demonstrate that the Ryzen 9 9955HX's additional cores translate directly into raw computational throughput.

Data encryption shows a 200.6% lead, 37,330 versus 12,418. This is a workload where both the core count and the larger L3 cache on the Ryzen 9 9955HX provide a measurable benefit. Data compression shows a 185.5% lead, 731,998 versus 256,420, and random string sorting shows a 185.8% lead, 77,890 versus 27,252. The 64 MB L3 cache on the Ryzen 9 9955HX versus 8 MB on the Ryzen AI 5 PRO 440 helps explain these large margins in memory-intensive tasks.

Multithread testing shows a 166.8% lead, 56,171 versus 21,054. Physics simulation shows a 143.1% lead, 2,720 versus 1,119. The smallest margin in the entire comparison is single-thread performance, where the Ryzen 9 9955HX scores 4,393 versus 3,785, a 16.1% lead. This indicates that the per-core architecture is similar, and the Ryzen 9 9955HX's advantage comes primarily from its higher boost clock of 5.40 GHz versus 4.80 GHz.

The average benchmark scores align with these head-to-head results. The Ryzen 9 9955HX averages 91,199, placing it in the 96th percentile of all CPUs. Its nearest rivals include the Intel Xeon 654 at 90,717 (0.5% behind) and the AMD Ryzen AI Max+ 392 at 90,541 (0.7% behind). The Ryzen AI 5 PRO 440 averages 41,208, in the 87th percentile. Its nearest rivals include the Intel Core Ultra 7 356H at 41,215 (0% difference) and the AMD Ryzen 9 5900X at 41,376 (0.4% ahead). The Ryzen 9 9955HX competes in a different performance class entirely.

Specification Differences

The two processors differ across nearly every specification category. Core count: 16 versus 6. Threads: 32 versus 12. Base clock: 2.50 GHz versus 2.00 GHz. Boost clock: 5.40 GHz versus 4.80 GHz. TDP: 55 W versus 28 W.

Socket: AMD Socket FL1 versus AMD Socket FP8. Codename: Fire Range versus Gorgon Point. Generation: Ryzen 9 (Zen 5, Fire Range) versus Ryzen AI PRO 400 (Zen 5 / Zen 5c). The Ryzen 9 9955HX uses a dual-chiplet design with a die size of 2x 70.6 mm² and 16,630 million transistors, while the Ryzen AI 5 PRO 440 uses a monolithic die of 195 mm².

Cache: L1 and L2 are identical at 80 KB per core and 1 MB per core, respectively. L3 differs sharply: 64 MB shared on the Ryzen 9 9955HX versus 8 MB on the Ryzen AI 5 PRO 440.

Memory support: DDR5 on the Ryzen 9 9955HX; DDR5 and LPDDR5X on the Ryzen AI 5 PRO 440. Both use dual-channel buses with 89.6 GB/s bandwidth and support ECC memory. PCIe: Gen 5 with 28 CPU-only lanes on the Ryzen 9 9955HX; Gen 4 with 16 CPU-only lanes on the Ryzen AI 5 PRO 440.

Integrated graphics: Radeon 610M on the Ryzen 9 9955HX; Radeon 840M on the Ryzen AI 5 PRO 440. The Ryzen 9 9955HX has an unlocked multiplier; the Ryzen AI 5 PRO 440 does not. Release dates differ as well: the Ryzen 9 9955HX launched on 2025-01-05, while the Ryzen AI 5 PRO 440 launched on 2026-01-04. Both remain in active production.