Intel Core 7 251E vs Intel Core Ultra 7 155UL Comparison

Head-to-Head Benchmarks

The recorded data for the Intel Core 7 251E and the Intel Core Ultra 7 155UL contains no direct head-to-head benchmark entries, and both processors carry a neutral database standing with identical percentile scores of 50 against all CPUs. Their average benchmark scores are also equal at zero, which means the database currently lacks measured performance deltas between these two parts. What can be assessed instead is the architectural potential each processor brings to the table, based on the listed core counts, clock speeds, and cache hierarchies.

The Core 7 251E fields 24 cores and 32 threads, while the Core Ultra 7 155UL manages 12 cores and 14 threads. That difference alone indicates a substantial advantage for the 251E in multi-threaded workloads. The 251E boosts to 5.60 GHz, which is 0.80 GHz higher than the 155UL's 4.80 GHz top speed. In single-thread responsiveness, the 251E should hold a clear edge, since higher boost clocks generally translate to faster per-core execution. The 155UL counters with a lower 1.70 GHz base clock versus the 251E's 2.10 GHz, reinforcing the same pattern: the 251E is configured for higher sustained throughput.

The cache allocations further separate these two designs. The Core 7 251E carries 36 MB of shared L3 cache, triple the 12 MB found on the Core Ultra 7 155UL. Larger L3 capacity typically reduces memory latency and improves hit rates in data-heavy workloads. The 251E also uses a 10 nm process, while the 155UL uses a denser 7 nm node, which suggests the 155UL may achieve better power efficiency per transistor. The 251E's die size is listed at 257 mm², while the 155UL's die size is not recorded in the database.

Both processors support dual-channel memory and share an identical memory bandwidth figure of 89.6 GB/s. That parity means memory throughput will not be the deciding factor between them. The 251E supports both DDR4 and DDR5, whereas the 155UL's memory support is listed as DDR5 with a dependency on the motherboard. The 251E also supports ECC memory, a feature absent from the 155UL. These differences point to distinct target environments despite both being classified as desktop parts.

Where Each One Wins

The Core 7 251E is positioned for heavy parallel workloads. Its 24 cores and 32 threads give it a raw thread-count advantage that should dominate rendering, compilation, and simulation tasks. The 5.60 GHz boost clock also makes it strong in lightly threaded applications where a single core's speed matters most. The 36 MB L3 cache supports workloads that repeatedly access large datasets, reducing the penalty of slower main memory. Its 65 W TDP indicates a higher power envelope, which is consistent with a part designed to sustain aggressive clock speeds across many cores.

The Core Ultra 7 155UL is built for efficiency. Its 15 W TDP is dramatically lower than the 251E's 65 W, making it the more suitable choice for compact systems or deployments where thermal output and energy draw are primary concerns. The 7 nm process node suggests a newer manufacturing technology that can deliver more performance per watt. Its integrated Arc Xe-LPG 64EU graphics unit is also a different class of iGPU compared to the UHD Graphics 770 on the 251E, which may matter for systems relying on the integrated display output for media or light graphics work.

The 155UL's smaller core count of 12 and lower boost clock of 4.80 GHz mean it will trail the 251E in raw compute, but its 112 KB L1 cache per core is larger than the 251E's 80 KB per core. That per-core cache advantage could improve performance in latency-sensitive single-threaded loops. The 155UL also uses the newer Socket 1851 platform, while the 251E uses Socket 1700, which matters for upgrade paths and motherboard availability.

Architecture Differences

The Core 7 251E comes from the Bartlett Lake generation, built on Intel's 10 nm process. It is a desktop processor with 24 cores, 32 threads, and a shared 36 MB L3 cache. Its L1 cache is 80 KB per core, and its L2 cache is 2 MB per core. The processor uses Socket 1700 and supports PCIe Gen 5 with 16 lanes from the CPU. Its integrated graphics are UHD Graphics 770. The 251E supports both DDR4 and DDR5 memory with dual-channel configuration, and it includes ECC memory support. Its launch MSRP is $384.

The Core Ultra 7 155UL belongs to the Core Ultra Series 1, built on the Meteor Lake architecture with a 7 nm process. It has 12 cores and 14 threads, with a shared 12 MB L3 cache. Its L1 cache is 112 KB per core, and its L2 cache is also 2 MB per core. This processor uses Socket 1851 and supports PCIe Gen 4 with 8 lanes from the CPU. Its integrated graphics are Arc Xe-LPG 64EU. Memory support is listed as DDR5, dependent on the motherboard, and the 155UL does not support ECC memory. Its launch MSRP is $426.

The node difference is notable: 10 nm for the 251E versus 7 nm for the 155UL. The 155UL's smaller node likely contributes to its much lower 15 W TDP. The 251E's higher 65 W TDP aligns with its larger core count and higher clocks. The 155UL's die size is not recorded, while the 251E's die size is 257 mm². Both processors are locked, with no unlocked multiplier.

The memory bandwidth is identical at 89.6 GB/s for both, and both use dual-channel memory buses. The 251E's broader memory compatibility (DDR4 and DDR5) gives it flexibility for older or newer platforms, while the 155UL's DDR5-only support ties it to current-generation motherboards. The 251E's ECC support is a clear differentiator for error-sensitive workloads, a feature the 155UL lacks entirely.

FAQ

Q: Which processor has more cores and threads?

A: The Intel Core 7 251E has 24 cores and 32 threads. The Intel Core Ultra 7 155UL has 12 cores and 14 threads.

Q: What are the boost clock differences?

A: The Core 7 251E boosts to 5.60 GHz, while the Core Ultra 7 155UL boosts to 4.80 GHz. The 251E is 0.80 GHz faster in boost clock.

Q: How does the cache size compare?

A: The Core 7 251E has 36 MB of shared L3 cache, while the Core Ultra 7 155UL has 12 MB. The 251E has 80 KB L1 per core, and the 155UL has 112 KB L1 per core. Both have 2 MB L2 per core.

Q: What is the TDP difference?

A: The Core 7 251E has a TDP of 65 W. The Core Ultra 7 155UL has a TDP of 15 W.

Q: Do both processors support ECC memory?

A: No. The Core 7 251E supports ECC memory. The Core Ultra 7 155UL does not.

Q: Which sockets do they use?

A: The Core 7 251E uses Intel Socket 1700. The Core Ultra 7 155UL uses Intel Socket 1851.

The Verdict

The data clearly separates these two processors into different roles. The Intel Core 7 251E is the performance-oriented part. It offers double the core count, more than double the threads, a higher boost clock, three times the L3 cache, and ECC support. Its 65 W TDP reflects the power budget required to feed those resources. For workloads that scale with cores and threads, the 251E is the obvious choice based on the recorded specifications.

The Intel Core Ultra 7 155UL is the efficiency-focused alternative. Its 15 W TDP is a fraction of the 251E's power draw, and its 7 nm process node points to a newer manufacturing approach. The 155UL uses the newer Socket 1851 platform and includes a different integrated graphics solution, Arc Xe-LPG 64EU. Its per-core L1 cache is larger, which could benefit certain single-threaded patterns, but its overall compute resources are far smaller.

There are no benchmark scores or rival comparisons in the database to confirm real-world performance deltas. The percentile scores are identical at 50 for both, and the average benchmark score is zero for each. That means the verdict rests entirely on the specification differences. The 251E is configured for throughput and responsiveness. The 155UL is configured for low power and modern platform integration. Each part wins in its intended domain, and the recorded data does not support a single universal recommendation.

Specification Differences

| Field | Intel Core 7 251E | Intel Core Ultra 7 155UL |

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

| Cores | 24 | 12 |

| Threads | 32 | 14 |

| Base Clock | 2.10 GHz | 1.70 GHz |

| Boost Clock | 5.60 GHz | 4.80 GHz |

| TDP | 65 W | 15 W |

| Socket | Intel Socket 1700 | Intel Socket 1851 |

| Codename | Bartlett Lake | Meteor Lake-PS |

| Generation | Core 7 (Bartlett Lake) | Ultra 7 (Meteor Lake-PS) |

| Process Node | 10 nm | 7 nm |

| Die Size | 257 mm² | Not recorded |

| L1 Cache | 80 KB (per core) | 112 KB (per core) |

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

| L3 Cache | 36 MB (shared) | 12 MB (shared) |

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

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

| ECC Memory | Yes | No |

| PCIe | Gen 5, 16 Lanes (CPU only) | Gen 4, 8 Lanes (CPU only) |

| Integrated Graphics | UHD Graphics 770 | Arc Xe-LPG 64EU |

| Release Date | 2025-01-12 | 2024-04-07 |

| Launch MSRP | $384 | $426 |

| Multiplier Unlocked | No | No |

| Part Number | SRQDUQ657 | SRN97 |