AMD Ryzen 9 9955HX vs Intel Core Ultra 5 250K Plus Comparison

The AMD Ryzen 9 9955HX and the Intel Core Ultra 5 250K Plus occupy very different corners of the processor market, yet their benchmark results create a surprisingly competitive head-to-head. The AMD chip is a 16-core, 32-thread mobile processor built for high-end laptops, while the Intel part is an 18-core, 18-thread desktop CPU aimed at mainstream desktop builds. The recorded data shows a split decision: the AMD Ryzen 9 9955HX wins 8 of the 15 head-to-head benchmark comparisons, while the Intel Core Ultra 5 250K Plus wins 7. The margins, however, tell a more nuanced story than the win count alone.

Head-to-Head Benchmarks

The AMD Ryzen 9 9955HX dominates the heavily multithreaded workloads. In Cinebench R15 multi-core, the AMD chip scores 5905 against Intel's 4640, a 27.3% advantage. The Cinebench R23 multi-core test shows a similar pattern: AMD scores 37159 versus 30867, a 20.4% lead. These are substantial gaps that reflect the AMD processor's ability to sustain high throughput across its 32 threads. The PassMark integer math test is where AMD is most dominant, scoring 212598 against Intel's 125091, a massive 70% difference. That is the single largest margin in the entire comparison. The PassMark extended instructions test also favors AMD by 30% (57946 versus 44565), and data compression shows AMD ahead by 28.7% (731998 versus 568721). The AMD chip also wins the multi-thread test (56171 versus 51596, an 8.9% margin) and random string sorting (77890 versus 69090, a 12.7% margin). Even in Cinebench R15 single-core, AMD edges ahead by a slim 2.4% (336 versus 328).

The Intel Core Ultra 5 250K Plus, despite having fewer threads, fights back in several specific workloads. The most striking Intel win is in the PassMark find prime numbers test, where Intel scores 486 against AMD's 287, a 40.9% advantage. This is a workload that clearly responds to Intel's architecture and clock strategy. Intel also wins decisively in floating-point math, scoring 162692 versus 136682, a 16% margin. The physics test favors Intel by 22.2% (3494 versus 2720). In Cinebench R23 single-core, Intel takes a smaller but meaningful win: 2261 versus 2174, a 3.8% lead. The PassMark single-thread test shows Intel ahead by 7.7% (4757 versus 4393). Intel also wins data encryption, scoring 42144 versus 37330, an 11.4% margin.

The average benchmark scores in the database place the AMD Ryzen 9 9955HX at 91199, while the Intel Core Ultra 5 250K Plus sits at 66855. The AMD chip's percentile ranking is 96 among all CPUs, versus 93 for the Intel part. The AMD processor's nearest rivals include the Intel Xeon 654 (0.5% higher average score) and the AMD Ryzen AI Max+ 392 (0.7% higher), while it trails the Intel Core Ultra 7 270K Plus and Intel Xeon 6520P by 2.8%. The Intel Core Ultra 5 250K Plus's nearest rivals are the AMD EPYC 4465P (0.1% lower) and the Intel Xeon 6515P (0.2% lower), with the Intel Core Ultra 9 275HX 0.9% ahead.

Architecture Differences

The two processors come from fundamentally different design philosophies. The AMD Ryzen 9 9955HX uses the Zen 5 architecture under the Fire Range codename, belonging to the 9000 series and the Ryzen 9 generation. It is built on a 4 nm process at TSMC, with a transistor count of 16,630 million spread across a dual-die design with each die measuring 70.6 mm². The Intel Core Ultra 5 250K Plus uses the Arrow Lake Refresh codename from the Core Ultra Series 2, built on a more advanced 3 nm process at the same foundry, TSMC. The Intel chip packs 17,800 million transistors on a single 243 mm² die.

Cache configurations diverge sharply. The AMD processor provides 80 KB of L1 cache per core, 1 MB of L2 cache per core, and a large 64 MB shared L3 cache. The Intel chip offers 192 KB of L1 cache per core, 3 MB of L2 cache per core, but only 30 MB of shared L3 cache. This means the AMD part has more than double the total L3 capacity, which likely contributes to its strong performance in data compression and integer-heavy workloads. The Intel part's larger per-core L2 cache (3 MB versus 1 MB) may help with its prime number and physics results.

The memory controllers also differ. Both support DDR5 and dual-channel memory, but the Intel chip has a higher memory bandwidth rating of 115.2 GB/s, compared to 89.6 GB/s for the AMD processor. Both support ECC memory. The PCIe implementations differ as well: AMD provides Gen 5 with 28 lanes from the CPU, while Intel provides Gen 5 with 20 lanes. The integrated graphics are different, with AMD using Radeon 610M and Intel using Arc Xe-LPG Graphics 64EU.

Where Each One Wins

The AMD Ryzen 9 9955HX is the clear choice for workloads that scale with thread count and cache capacity. The data shows its 32 threads deliver a 20.4% advantage in Cinebench R23 multi-core and a 27.3% advantage in Cinebench R15 multi-core. The 70% lead in integer math suggests the AMD architecture handles branch-heavy, logic-intensive code exceptionally well. Data compression, which relies heavily on cache and memory throughput, shows a 28.7% AMD advantage. The 30% lead in extended instructions points to strong SIMD and specialized instruction handling. For users running video encoding, 3D rendering, software compilation, or database workloads that use many threads, the AMD Ryzen 9 9955HX is the stronger performer based on the recorded benchmarks.

The Intel Core Ultra 5 250K Plus wins in specific single-thread and latency-sensitive tasks. The 40.9% lead in prime number finding and the 22.2% lead in physics indicate that Intel's per-core performance, combined with its higher base clock of 4.20 GHz versus AMD's 2.50 GHz, makes it faster for workloads that do not parallelize well. The 16% win in floating-point math shows Intel's FP units are more efficient for scientific or simulation code. The 7.7% lead in single-thread PassMark and 3.8% lead in Cinebench R23 single-core confirm that for lightly threaded applications, the Intel chip offers better responsiveness. Data encryption also favors Intel by 11.4%, which may matter for security-focused tasks.

Specification Differences

The most apparent difference is the core and thread layout. The AMD Ryzen 9 9955HX has 16 cores and 32 threads, while the Intel Core Ultra 5 250K Plus has 18 cores but only 18 threads, meaning it has no hyperthreading. The base clocks differ substantially: AMD runs at 2.50 GHz, Intel at 4.20 GHz. Boost clocks are closer, with AMD at 5.40 GHz and Intel at 5.30 GHz. The TDP ratings reflect their different market segments: AMD is rated at 55 W, suitable for mobile, while Intel is rated at 125 W, designed for desktop power delivery.

The sockets are incompatible, with AMD using Socket FL1 and Intel using Socket 1851. The process nodes differ at 4 nm for AMD and 3 nm for Intel, both from TSMC. Transistor counts are close, with Intel slightly higher at 17,800 million versus 16,630 million. Die sizes tell a different story: AMD uses two smaller dies (each 70.6 mm²) while Intel uses a single larger die (243 mm²). Cache sizes differ as detailed above. Memory bandwidth favors Intel at 115.2 GB/s versus 89.6 GB/s. PCIe lanes favor AMD at 28 lanes versus Intel's 20, both Gen 5. Integrated graphics are not comparable, with AMD using Radeon 610M and Intel using Arc Xe-LPG Graphics 64EU. The release dates are distinct, with AMD launching on 2025-01-05 and Intel on 2026-03-10. Both processors have unlocked multipliers. The Intel part has a launch MSRP of $199. The AMD part number is 100-000001028, and the Intel part number is SA4UZ.

FAQ

Q: Which processor has more cores and threads?

A: The AMD Ryzen 9 9955HX has 16 cores and 32 threads. The Intel Core Ultra 5 250K Plus has 18 cores and 18 threads.

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

A: The largest margin is in PassMark integer math, where the AMD Ryzen 9 9955HX scores 212598 versus Intel's 125091, a 70% difference.

Q: Does the Intel processor win any multi-core benchmarks?

A: No. The Intel Core Ultra 5 250K Plus loses the Cinebench R15 multi-core test (4640 versus 5905) and the Cinebench R23 multi-core test (30867 versus 37159). It also loses the PassMark multi-thread test (51596 versus 56171).

Q: Which processor has a higher boost clock?

A: The AMD Ryzen 9 9955HX has a boost clock of 5.40 GHz, while the Intel Core Ultra 5 250K Plus has a boost clock of 5.30 GHz.

Q: How do their average benchmark scores compare?

A: The AMD Ryzen 9 9955HX has an average benchmark score of 91199, while the Intel Core Ultra 5 250K Plus has an average score of 66855.

Q: Which processor supports ECC memory?

A: Both the AMD Ryzen 9 9955HX and the Intel Core Ultra 5 250K Plus support ECC memory. Both also support DDR5 memory with dual-channel configuration.