Intel Core Ultra 5 250K Plus vs Intel Core Ultra 7 356H Comparison

Head-to-Head Benchmarks

The benchmark data shows a decisive overall victory for the Intel Core Ultra 5 250K Plus, winning all 17 recorded head-to-head comparisons against the Intel Core Ultra 7 356H. The average benchmark score of 66,855 for the desktop processor versus 41,215 for the mobile part places them 62.3% apart in raw aggregate performance, a gap that appears consistently across every workload category.

The largest advantage comes in multi-core rendering workloads. In Cinebench R23 multi-core, the Ultra 5 250K Plus scores 30,867 against 18,395 for the Ultra 7 356H, a 67.8% lead. Cinebench R20 multi-core shows a similar pattern at 51.7% ahead, with scores of 18,442 versus 12,153. Cinebench R15 multi-core delivers a 51.9% advantage, 4,640 versus 3,055. These results indicate that the desktop part scales substantially better across all cores under sustained rendering load.

The single-core gap is narrower but still favors the Ultra 5 250K Plus in every test. Cinebench R23 single-core shows 2,261 versus 2,040, a 10.8% edge. Cinebench R20 single-core records 2,603 versus 1,715, which is a 51.8% advantage, an unusually large margin for a single-threaded workload. Cinebench R15 single-core shows 328 versus 303, an 8.3% lead. PassMark single-thread records 4,757 versus 4,072, a 16.8% advantage.

Encryption and compression workloads heavily favor the desktop chip. PassMark data encryption shows 42,144 versus 26,345, a 60% lead. PassMark data compression records 568,721 versus 336,177, a 69.2% advantage, the largest delta in the entire benchmark set. Random string sorting follows at 68.6% ahead, with scores of 69,090 versus 40,990. Extended instruction performance is 59.7% higher, at 44,565 versus 27,898.

Floating-point and integer math also show consistent leads. PassMark floating point math records 162,692 versus 103,128, a 57.8% advantage. Integer math scores 125,091 versus 83,111, putting the Ultra 5 250K Plus 50.5% ahead. The prime number finding workload shows a 48.6% gap, 486 versus 327. PassMark multi-thread scores 51,596 versus 33,978, a 51.9% advantage. Physics simulation shows the smallest overall gap at 20.7%, with 3,494 versus 2,895.

The data indicates the Ultra 5 250K Plus is not merely faster but consistently faster across every measured discipline. The mobile part does not win a single subtest, even in workloads where lower power parts typically close the gap, such as single-thread integer tasks. The desktop chip's 93rd percentile ranking among all CPUs versus the mobile chip's 87th percentile reinforces this overall positioning.

Architecture Differences

The two processors come from different Intel series generations. The Ultra 5 250K Plus belongs to Core Ultra Series 2, built on the Arrow Lake Refresh codename, while the Ultra 7 356H is from Core Ultra Series 3, using the Panther Lake architecture and Panther Lake-H generation designation. Both use a 3 nm process node, but the foundry differs: TSMC produces the desktop chip, while Intel fabricates the mobile part.

The desktop processor uses 18 cores and 18 threads, while the mobile processor uses 16 cores and 16 threads. Neither part uses simultaneous multithreading. The Ultra 5 250K Plus has a base clock of 4.20 GHz and a boost clock of 5.30 GHz. The Ultra 7 356H runs at 1.90 GHz base and 4.70 GHz boost. The desktop part is unlocked for overclocking, and the mobile part is locked.

Cache configurations differ meaningfully. Both share 192 KB of L1 per core. The L2 cache is 3 MB per core on the desktop part versus 2.5 MB per core on the mobile part. Shared L3 totals 30 MB on the Ultra 5 250K Plus versus 18 MB on the Ultra 7 356H. This 12 MB L3 difference and the per-core L2 advantage contribute to the desktop chip's performance headroom in cache-sensitive workloads.

Socket and platform separation is complete. The Ultra 5 250K Plus uses Intel Socket 1851 and targets the desktop market segment. The Ultra 7 356H uses Intel BGA 2540 and is a mobile part. The desktop chip provides Gen 5 PCIe with 20 CPU lanes, while the mobile part provides Gen 5 with 12 CPU lanes. Both support dual-channel memory at 115.2 GB/s bandwidth, but the desktop chip supports DDR5 only, while the mobile chip supports DDR5 and LPDDR5X. ECC memory is supported on the desktop part and not on the mobile part.

Integrated graphics differ as well. The Ultra 5 250K Plus carries Arc Xe-LPG Graphics with 64 execution units. The Ultra 7 356H uses Intel Xe3 Graphics. Transistor count and die size are recorded for the desktop part at 17,800 million transistors and 243 mm², while the mobile part does not have those figures listed in the database.

The power envelope is dramatically different. The desktop part has a 125 TDP, while the mobile part has a 25 TDP. This 100 watt difference explains much of the performance gap, though architectural differences also play a role. The desktop part was released on 2026-03-10, while the mobile part appeared earlier on 2026-01-04. The desktop part has a launch MSRP of $199; the mobile part has no recorded launch MSRP.

FAQ

Q: Which processor is faster in multi-core rendering benchmarks?

A: The Intel Core Ultra 5 250K Plus wins all multi-core Cinebench tests. It leads by 51.9% in R15, 51.7% in R20, and 67.8% in R23 multi-core.

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

A: The desktop part wins every single-thread test. The smallest margin is 8.3% in Cinebench R15 single-core; the largest is 51.8% in Cinebench R20 single-core. PassMark single-thread shows a 16.8% advantage.

Q: Do the two chips use the same manufacturing process?

A: Both use a 3 nm process node, but different foundries. TSMC produces the Ultra 5 250K Plus, while Intel fabricates the Ultra 7 356H.

Q: What memory types does each processor support?

A: The Ultra 5 250K Plus supports DDR5 only. The Ultra 7 356H supports both DDR5 and LPDDR5X. Both use dual-channel memory at 115.2 GB/s bandwidth.

Q: Is the mobile chip competitive in any benchmark category?

A: The recorded data shows no wins for the Ultra 7 356H. The closest result is PassMark physics at a 20.7% gap; every other test shows a lead of at least 48.6% for the desktop chip.

Q: What are the core and thread counts?

A: The Ultra 5 250K Plus has 18 cores and 18 threads. The Ultra 7 356H has 16 cores and 16 threads. Neither uses hyper-threading.

The Verdict

The benchmark data supports a clear separation of roles. The Intel Core Ultra 5 250K Plus is the higher-performance processor in every recorded measurement. Its 18 cores, 30 MB of L3 cache, 5.30 GHz boost clock, and 125 TDP combine to deliver average scores 62.3% higher than the mobile part. The 93rd percentile ranking among all CPUs places it firmly in the upper tier of the database.

The Intel Core Ultra 7 356H occupies a different position. Its 16 cores, 18 MB L3, and 4.70 GHz boost clock operate within a 25 TDP envelope, which is one-fifth the power budget of the desktop part. The 87th percentile ranking still places it above most CPUs, and its nearest rivals include the AMD Ryzen 9 5900X with a 0.4% lower average score. For users constrained by mobile power limits, the 356H delivers competitive performance within its class.

The data does not suggest the 356H is a poor processor; it suggests the 250K Plus is a different class of part entirely. The desktop chip's nearest rivals are server and workstation processors like the AMD EPYC 4465P and Intel Xeon 6515P, with deltas under 0.2%. The mobile chip's nearest rivals are other mobile and older desktop parts. These peer groups confirm that the two chips are not direct competitors despite both carrying the Core Ultra name.

The 250K Plus is the choice for maximum throughput, unlocked overclocking, ECC memory support, and desktop expansion via 20 PCIe Gen 5 lanes. The 356H is the choice for mobile systems requiring DDR5 or LPDDR5X memory, a 25 TDP power profile, and a locked multiplier with Intel Xe3 graphics. The performance gap is consistent and large, but the power and form factor differences make each part appropriate for its intended market segment.

Specification Differences

| Specification | Intel Core Ultra 5 250K Plus | Intel Core Ultra 7 356H |

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

| Series | Core Ultra Series 2 | Core Ultra Series 3 |

| Cores | 18 | 16 |

| Threads | 18 | 16 |

| Base clock | 4.20 GHz | 1.90 GHz |

| Boost clock | 5.30 GHz | 4.70 GHz |

| TDP | 125 | 25 |

| Socket | Intel Socket 1851 | Intel BGA 2540 |

| Architecture | Arrow Lake Refresh | Panther Lake |

| Foundry | TSMC | Intel |

| L2 cache | 3 MB (per core) | 2.5 MB (per core) |

| L3 cache | 30 MB (shared) | 18 MB (shared) |

| Memory support | DDR5 | DDR5, LPDDR5X |

| ECC memory | Supported | Not supported |

| PCIe | Gen 5, 20 lanes (CPU only) | Gen 5, 12 lanes (CPU only) |

| Integrated graphics | Arc Xe-LPG Graphics 64EU | Intel Xe3 Graphics |

| Market segment | Desktop | Mobile |

| Multiplier unlocked | Yes | No |

| Release date | 2026-03-10 | 2026-01-04 |

| Launch MSRP | $199 | Not recorded |

| Transistors | 17,800 million | Not recorded |

| Die size | 243 mm² | Not recorded |

Both processors share the same 3 nm process node, 192 KB L1 per core, dual-channel memory bus, and 115.2 GB/s memory bandwidth. The desktop part offers more cores, more cache, higher clocks, a larger power budget, and additional platform features. The mobile part offers memory flexibility with LPDDR5X support and a significantly lower power envelope for portable systems.