Intel Core i9-12900K vs Intel Core Ultra 7 265H Comparison

The Intel Core i9-12900K and the Intel Core Ultra 7 265H are both 16-core processors that land in the 88th percentile of all CPUs, yet they are engineered for entirely different environments. The i9-12900K is a desktop part from the Alder Lake generation, while the 265H is a mobile chip from the Arrow Lake generation. The benchmark data reveals a clear split: the i9-12900K dominates in heavily multithreaded workloads, taking 10 of the 17 head-to-head tests, while the Core Ultra 7 265H counters with 7 wins, mostly in single-threaded and specialized tasks. The following analysis breaks down where each processor excels, the architectural reasons for those differences, and what the numbers mean for a potential buyer.

Where Each One Wins

The Intel Core i9-12900K is the clear victor in raw multi-core throughput. Its largest victory comes in PassMark integer math, where it scores 139,090 against the 265H’s 85,479, a massive 62.7% advantage. This trend continues across Cinebench multi-core tests, with the i9-12900K leading by 35.7% in R15 (4057 vs 2989), 21% in R20 (14679 vs 12131), and 31% in R23 (26125 vs 19940). The desktop chip also wins decisively in PassMark data compression (537,341 vs 334,711, a 60.5% lead), random string sorting (57,094 vs 40,742, a 40.1% lead), and extended instructions (33,682 vs 26,805, a 25.7% lead). For workloads like video rendering, code compilation, or data processing that scale with thread count, the i9-12900K is the stronger performer.

The Intel Core Ultra 7 265H, despite its lower power envelope, wins in several efficiency-oriented and single-threaded metrics. Its most striking victory is in PassMark find prime numbers, where it scores 335 versus the i9-12900K’s 147, a 56.1% advantage. It also edges ahead in floating-point math (109,123 vs 105,471, a 3.3% lead) and physics (2,497 vs 2,219, an 11.1% lead). In Cinebench single-core tests, the 265H wins R15 (307 vs 289, a 5.9% lead) and R23 (2080 vs 2004.5, a 3.6% lead), though it loses R20 single-core by 21% (1712 vs 2072). The PassMark single-thread score also favors the 265H at 4,334 versus 4,136, a 4.6% lead. This indicates the mobile chip has superior per-core efficiency, making it better suited for lightly threaded tasks and battery-conscious workloads.

Architecture Differences

The two processors represent distinct architectural eras. The Intel Core i9-12900K uses the Alder Lake architecture on a 10 nm process node, built by Intel, with a die size of 215 mm². The Core Ultra 7 265H uses the newer Arrow Lake architecture on a 3 nm process node, built by TSMC. This process advantage helps explain the 265H’s higher single-thread performance despite a much lower 28W TDP, compared to the i9-12900K’s 125W TDP.

Core and cache configurations also differ significantly. Both have 16 cores, but the i9-12900K supports 24 threads (implying 8 hyper-threaded performance cores), while the 265H has only 16 threads (no hyper-threading). The cache hierarchy is reversed in size per core: the i9-12900K has 80 KB of L1 per core and 1.25 MB of L2 per core, while the 265H has 192 KB of L1 per core and 3 MB of L2 per core. However, the i9-12900K has a larger shared L3 cache at 30 MB versus 24 MB on the 265H. The 265H’s larger per-core caches likely contribute to its single-thread efficiency.

Memory support also diverges. The i9-12900K supports DDR4 and DDR5 with a memory bandwidth of 76.8 GB/s, while the 265H supports DDR5 and LPDDR5X with a higher bandwidth of 102.4 GB/s. Both are dual-channel and support ECC memory. The i9-12900K offers more PCIe lanes for CPU-only use (16 lanes of Gen 5) versus the 265H’s 8 lanes of Gen 5. The desktop chip has an unlocked multiplier, whereas the 265H is locked.

FAQ

Q: Which processor has better single-core performance?

A: The Intel Core Ultra 7 265H generally wins. It leads in Cinebench R15 single-core (307 vs 289), R23 single-core (2080 vs 2004.5), and PassMark single-thread (4334 vs 4136). However, the i9-12900K wins Cinebench R20 single-core (2072 vs 1712).

Q: Is the Intel Core i9-12900K better for multi-threaded tasks?

A: Yes, clearly. The i9-12900K leads in all Cinebench multi-core tests (R15, R20, R23) and in PassMark multithread (41213 vs 34027). Its biggest multi-core win is in PassMark integer math, with a 62.7% advantage.

Q: What makes the Core Ultra 7 265H more efficient?

A: The 265H has a 28W TDP versus the i9-12900K’s 125W TDP. It is built on a more advanced 3 nm process by TSMC, while the i9-12900K uses Intel’s 10 nm process. This allows the 265H to achieve higher single-thread scores in several tests with much less power draw.

Q: Do both processors support the same memory types?

A: No. The i9-12900K supports DDR4 and DDR5, while the Core Ultra 7 265H supports DDR5 and LPDDR5X. The 265H also has a higher memory bandwidth at 102.4 GB/s versus 76.8 GB/s for the i9-12900K.

Q: Which CPU has more threads?

A: The Intel Core i9-12900K has 24 threads, while the Core Ultra 7 265H has 16 threads. Both have 16 cores, but the i9-12900K uses hyper-threading to double thread count on its performance cores.

Q: Are these processors in the same performance percentile?

A: Yes, both are in the 88th percentile of all CPUs. Their average benchmark scores are close: 42,335 for the i9-12900K and 41,621 for the 265H, a difference of about 1.7%.

Specification Differences

| Specification | Intel Core i9-12900K | Intel Core Ultra 7 265H |

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

| Threads | 24 | 16 |

| Base Clock | 3.20 GHz | 2.20 GHz |

| Boost Clock | 5.20 GHz | 5.30 GHz |

| TDP | 125 W | 28 W |

| Socket | Intel Socket 1700 | Intel BGA 2049 |

| Architecture | Alder Lake | Arrow Lake |

| Codename | Alder Lake-S | Arrow Lake-H |

| Process Node | 10 nm | 3 nm |

| Foundry | Intel | TSMC |

| Die Size | 215 mm² | Not specified |

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

| L2 Cache | 1.25 MB (per core) | 3 MB (per core) |

| L3 Cache | 30 MB (shared) | 24 MB (shared) |

| Memory Support | DDR4, DDR5 | DDR5, LPDDR5X |

| Memory Bandwidth | 76.8 GB/s | 102.4 GB/s |

| PCIe Lanes | Gen 5, 16 Lanes | Gen 5, 8 Lanes |

| Integrated Graphics | UHD Graphics 770 | Arc Graphics 140T |

| Market Segment | Desktop | Mobile |

| Release Date | 2021-11-03 | 2025-01-12 |

| Launch MSRP | $599 | Not specified |

| Multiplier Unlocked | Yes | No |

| Part Number | SRL4H | SRQAQ |

Head-to-Head Benchmarks

The largest wins for the Intel Core i9-12900K are staggering. In PassMark integer math, it outperforms the 265H by 62.7% (139,090 vs 85,479). PassMark data compression shows a 60.5% advantage (537,341 vs 334,711). Cinebench R23 multi-core results give the i9-12900K a 31% lead (26,125 vs 19,940), while Cinebench R15 multi-core shows a 35.7% gap (4,057 vs 2,989). PassMark random string sorting is another major win, with a 40.1% delta (57,094 vs 40,742). The i9-12900K also wins in PassMark extended instructions (25.7% lead), multithread (21.1% lead), data encryption (13.7% lead), and Cinebench R20 multi-core (21% lead). These results underscore the desktop chip’s dominance in parallel workloads.

The Intel Core Ultra 7 265H’s wins are more modest in percentage but reveal its per-core strengths. The most extreme is PassMark find prime numbers, where it beats the i9-12900K by 56.1% (335 vs 147). In PassMark physics, it has an 11.1% advantage (2,497 vs 2,219). Its single-thread wins are smaller: Cinebench R15 single-core is a 5.9% lead (307 vs 289), PassMark single-thread is a 4.6% lead (4,334 vs 4,136), and Cinebench R23 single-core is a 3.6% lead (2,080 vs 2,004.5). PassMark floating-point math goes to the 265H by a slim 3.3% margin (109,123 vs 105,471). The only test where the 265H loses single-core is Cinebench R20, where the i9-12900K wins by 21% (2,072 vs 1,712).

The Verdict

The data presents a straightforward choice based on workload and platform. The Intel Core i9-12900K is the pick for users who need maximum multi-threaded performance in a desktop system. Its 24 threads, larger 30 MB L3 cache, and higher 125W TDP translate into commanding leads in integer math (62.7% ahead), data compression (60.5% ahead), and Cinebench multi-core tests (31% ahead in R23). It also offers more PCIe lanes (16 vs 8) and supports DDR4 in addition to DDR5, providing flexibility for builders. The unlocked multiplier is a further advantage for enthusiasts, though its $599 launch MSRP reflects a premium desktop positioning.

The Intel Core Ultra 7 265H is the appropriate choice for a mobile or compact system where power efficiency and single-thread responsiveness are paramount. Its 28W TDP is dramatically lower, yet it still achieves higher scores in PassMark single-thread (4,334 vs 4,136) and Cinebench R23 single-core (2,080 vs 2,004.5). The 3 nm process and larger per-core caches (192 KB L1, 3 MB L2) explain its efficiency. Its higher memory bandwidth (102.4 GB/s) and support for LPDDR5X make it suited for thin-and-light laptops. The 265H also wins in specialized tasks like prime number finding (56.1% ahead) and physics (11.1% ahead), suggesting better per-core instruction efficiency.

Benchmark results indicate both processors are in the same overall percentile (88th), with average scores within 1.7% of each other. The i9-12900K wins 10 of the 17 head-to-head tests, but the 265H wins 7. The verdict is clear: choose the i9-12900K for desktop multi-core workloads, and choose the Core Ultra 7 265H for mobile efficiency and single-thread performance.