Intel Core i9-11900 vs Intel Core Ultra 7 155H Comparison

The Intel Core Ultra 7 155H and the Intel Core i9-11900 occupy nearly identical positions in the database rankings, with average benchmark scores of 32697 and 32226 respectively, yet they arrive there by completely different routes. One is a Meteor Lake mobile chip built on a 7 nm process with 16 cores, the other an end-of-life Rocket Lake desktop flagship on 14 nm with 8 cores. The head-to-head data shows the Ultra 7 winning 11 of 17 recorded tests, but the i9-11900 dominates several single-threaded workloads by wide margins, which makes this a more nuanced comparison than the aggregate scores suggest.

Head-to-Head Benchmarks

The single largest win in the entire dataset belongs to the Core Ultra 7 155H: in PassMark Find Prime Numbers it scores 113 against 63, a 79.4% advantage. PassMark Physics tells a similar story, with the Ultra 7 at 1727 versus 977 for the i9-11900, a 76.8% gap. These are workloads where thread count matters, and the 155H's 22 threads against 16 clearly pay off.

Floating point math also leans heavily toward the newer chip: 63703 versus 48948, a 30.1% lead. Cinebench R15 multi-core follows the same pattern, with the 155H posting 2450 against 1913, a 28.1% advantage. Data encryption goes to the 155H by 17.3% (16358 versus 13942), PassMark multithread by 10.8% (24873 versus 22456), and both Cinebench R20 tests by exactly 9.8% each way: 8754 versus 7973 in multi-core, and 1235 versus 1125 in single-core.

The i9-11900's counterpunch comes in per-core throughput. Its most dramatic win is Cinebench R23 single-core, where it scores 2680 against 1743, a 35% lead for the Rocket Lake part. Cinebench R23 multi-core also goes its way at 18985 versus 15028, a 20.8% advantage, making R23 the one rendering generation where the desktop chip sweeps both columns. PassMark Extended Instructions favors the i9 by 16.3% (19654 versus 16456), Cinebench R15 single-core by 5.6% (270 versus 255), Random String Sorting by 3.2% (33054 versus 31990), and Data Compression by 2.7% (285159 versus 277353). PassMark single-thread narrowly favors the 155H at 3468 versus 3373, a 2.8% edge, which sits oddly against the R23 single-core result and suggests the two single-threaded methodologies measure different aspects of core performance.

Curiously, despite the 155H's 11 wins against 6, its percentile against all CPUs in the database is 83 versus 82 for the i9-11900, a one-point gap. Its nearest rivals by average score include the Intel Core i5-14600T (32707, 0% delta), AMD Ryzen AI 7 PRO 360 (32662, 0.1%), AMD Ryzen 5 7400F (32750, -0.2%), and AMD Ryzen 7 PRO 6850H (32812, -0.4%). The i9-11900 clusters with the AMD Ryzen 7 PRO 8840U (32233, 0%), Intel Core i5-14400F (32279, -0.2%), Intel Core i7-12800H (32121, 0.3%), and Intel Core i5-14400 (32115, 0.3%). Both chips therefore sit in effectively the same performance bracket overall.

Architecture Differences

These processors come from different eras and different market segments. The Core Ultra 7 155H is a Meteor Lake mobile processor released on December 13, 2023, fabricated on Intel's 7 nm process, soldered into an Intel BGA 2049 package with no socket upgrade path. The Core i9-11900 is a Rocket Lake desktop processor released on March 15, 2021, built on the 14 nm process, using Intel Socket 1200. The i9's die size is recorded at 276 mm², while no die size or transistor count is recorded for the 155H.

The core topology diverges sharply. The 155H carries 16 cores and 22 threads, a hybrid arrangement reflected in its uneven core-to-thread ratio. The i9-11900 has 8 cores and 16 threads, a uniform topology. Clock behavior also differs in opposite directions: the 155H has the higher base clock at 3.80 GHz versus 2.50 GHz, while the i9-11900 boosts higher at 5.20 GHz versus 4.80 GHz. That 5.20 GHz boost is consistent with the i9's strong single-core results in Cinebench R23.

Cache hierarchy favors the newer chip across every level: 112 KB of L1 per core versus 64 KB, 2 MB of L2 per core versus 512 KB, and 24 MB of shared L3 versus 16 MB. Memory support also splits them, with the 155H using DDR5 (noting motherboard dependency) on a dual-channel bus with 89.6 GB/s of bandwidth, and the i9-11900 using DDR4, dual-channel, at 51.2 GB/s. Neither supports ECC.

Platform connectivity is a genuine trade-off. The 155H offers PCIe Gen 5 but only 8 CPU lanes, while the i9-11900 offers PCIe Gen 4 with 20 CPU lanes. A desktop builder attaching multiple add-in cards gets more lanes from the older chip, while the 155H provides the newer standard for the lanes it has. Integrated graphics differ substantially: Arc Xe-LPG with 128 execution units on the 155H against UHD Graphics 750 on the i9-11900. Power envelopes reflect their segments: a 28 W TDP for the mobile part against 65 W for the desktop part. Neither has an unlocked multiplier. The 155H remains in active production; the i9-11900 is end-of-life.

FAQ

Q: Which CPU is faster overall?

A: The Core Ultra 7 155H wins 11 of 17 head-to-head tests and posts the higher average benchmark score, 32697 versus 32226, but the gap is small enough that both sit within one percentile point of each other (83 versus 82) against the full database.

Q: Which CPU is better for single-threaded workloads?

A: It depends on the test. The i9-11900 leads Cinebench R23 single-core by 35% (2680 versus 1743) and Cinebench R15 single-core by 5.6% (270 versus 255). The 155H counters with wins in Cinebench R20 single-core by 9.8% (1235 versus 1125) and PassMark single-thread by 2.8% (3468 versus 3373).

Q: Which CPU is better for heavily multi-threaded workloads?

A: Mostly the 155H. It wins Cinebench R15 multi-core by 28.1%, floating point math by 30.1%, prime finding by 79.4%, physics by 76.8%, and PassMark multithread by 10.8%. The exception is Cinebench R23 multi-core, where the i9-11900 leads by 20.8% (18985 versus 15028).

Q: Do these CPUs use the same memory?

A: No. The 155H supports DDR5 with 89.6 GB/s of bandwidth on a dual-channel bus, while the i9-11900 supports DDR4 with 51.2 GB/s on a dual-channel bus.

Q: Can either CPU be overclocked?

A: No. Both have locked multipliers.

Q: Which platform has more PCIe lanes?

A: The i9-11900, with 20 CPU lanes at Gen 4. The 155H offers 8 CPU lanes at Gen 5, so the older chip provides more lanes while the newer chip provides the faster standard.

The Verdict

The data supports the 155H for anyone whose workload scales with threads: rendering under Cinebench R15 and R20, physics simulation, prime computation, floating point math, encryption, and general multithreaded throughput all favor it, several by margins exceeding 28%. Its 16 cores, 22 threads, larger caches at every level, and higher memory bandwidth explain those results, and it achieves them within a 28 W envelope.

The i9-11900 remains the stronger choice in a narrower set of cases. Its 35% Cinebench R23 single-core lead and 20.8% R23 multi-core lead show the older architecture's high 5.20 GHz boost and uniform 8-core topology still delivering in that specific test generation, and it also wins extended instructions, data compression, string sorting, and R15 single-core. Buyers who need 20 PCIe Gen 4 lanes for add-in cards, or who already have a DDR4 dual-channel platform on Socket 1200, get more connectivity from the desktop part.

Because both land within roughly half a percent of each other on average score, neither is a blanket upgrade. The 155H is the better all-around performer by win count and offers the newer platform features (DDR5, Gen 5, stronger integrated graphics) while remaining in active production. The i9-11900 is end-of-life and its advantages are concentrated in per-core and R23-specific results.

Specification Differences

| Field | Intel Core Ultra 7 155H | Intel Core i9-11900 |

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

| Series | Core Ultra Series 1 | Core 11th Gen |

| Cores | 16 | 8 |

| Threads | 22 | 16 |

| Base Clock | 3.80 GHz | 2.50 GHz |

| Boost Clock | 4.80 GHz | 5.20 GHz |

| TDP | 28 W | 65 W |

| Socket | Intel BGA 2049 | Intel Socket 1200 |

| Architecture / Codename | Meteor Lake | Rocket Lake |

| Process Node | 7 nm | 14 nm |

| L1 Cache (per core) | 112 KB | 64 KB |

| L2 Cache (per core) | 2 MB | 512 KB |

| L3 Cache (shared) | 24 MB | 16 MB |

| Memory Support | DDR5 (depends on motherboard) | DDR4 |

| Memory Bandwidth | 89.6 GB/s | 51.2 GB/s |

| PCIe | Gen 5, 8 lanes (CPU only) | Gen 4, 20 lanes (CPU only) |

| Integrated Graphics | Arc Xe-LPG 128EU | UHD Graphics 750 |

| Market Segment | Mobile | Desktop |

| Production Status | Active | End-of-life |

| Release Date | December 13, 2023 | March 15, 2021 |

| Die Size | Not recorded | 276 mm² |

| Average Benchmark Score | 32697 | 32226 |

| Percentile vs All CPUs | 83 | 82 |