Intel Core 7 251E vs Intel Core Ultra 7 255HX Comparison
Intel Core 7 251E
Core Ultra 7 255HX
PERFORMANCE BENCHMARKS
Analysis: Intel Core 7 251E vs Intel Core Ultra 7 255HX
FAQ
Q: What are the core and thread counts for each processor?
A: The Intel Core 7 251E has 24 cores and 32 threads, while the Intel Core Ultra 7 255HX has 20 cores and 20 threads. The Core 7 251E provides more parallel threads, but the Core Ultra 7 255HX uses a different thread model.
Q: Which processor has the higher boost clock?
A: The Intel Core 7 251E boosts to 5.60 GHz, while the Intel Core Ultra 7 255HX boosts to 5.20 GHz. The 251E holds a 0.40 GHz advantage in maximum single-core frequency.
Q: Do both processors support DDR5 memory?
A: The Intel Core 7 251E supports both DDR4 and DDR5, whereas the Intel Core Ultra 7 255HX supports DDR5 only. The 251E offers broader memory compatibility.
Q: What is the process node for each chip?
A: The Intel Core 7 251E uses a 10 nm process from Intel, while the Intel Core Ultra 7 255HX uses a 3 nm process fabricated by TSMC. The 255HX uses a significantly smaller transistor geometry.
Q: Which processor has ECC memory support?
A: The Intel Core 7 251E supports ECC memory, while the Intel Core Ultra 7 255HX does not. This makes the 251E relevant for error-sensitive workloads.
Q: What is the average benchmark score for the Core Ultra 7 255HX?
A: The Core Ultra 7 255HX has an average benchmark score of 62738, placing it in the 93rd percentile among all CPUs. Its closest rival is the AMD Ryzen AI Embedded P185 with an average score of 62839, a delta of -0.2%.
Architecture Differences
The Intel Core 7 251E and Intel Core Ultra 7 255HX represent two distinct design approaches within Intel's lineup. The 251E is built on the Bartlett Lake architecture and uses a 10 nm process node fabricated by Intel. The 255HX is based on the Arrow Lake architecture, specifically Arrow Lake-HX, and uses a 3 nm process node from TSMC. The 255HX integrates 17,800 million transistors on a 243 mm² die, while the 251E has a 257 mm² die size with no transistor count listed in the database.
The memory support differs substantially. The 251E supports both DDR4 and DDR5 memory over a dual-channel bus, with a memory bandwidth of 89.6 GB/s. The 255HX supports only DDR5, also dual-channel, but achieves 102.4 GB/s of memory bandwidth. The 255HX delivers 12.8 GB/s more bandwidth, which can influence memory-intensive workloads.
Cache hierarchies also diverge. The 251E provides 80 KB of L1 cache per core, 2 MB of L2 cache per core, and 36 MB of shared L3 cache. The 255HX offers 192 KB of L1 per core, 3 MB of L2 per core, and 30 MB of shared L3. The 255HX has larger per-core caches, while the 251E has more total L3 cache.
The PCIe capabilities are not identical. The 251E exposes Gen 5 with 16 lanes from the CPU, while the 255HX exposes Gen 5 with 20 lanes from the CPU. The 255HX has more CPU-attached PCIe lanes. Integrated graphics differ as well: the 251E uses UHD Graphics 770, while the 255HX uses Arc Xe-LPG Graphics 64EU.
Form factors and sockets separate these chips further. The 251E is a desktop processor on Intel Socket 1700 with a 65 W TDP. The 255HX is a mobile processor on Intel BGA 2114 with a 55 W TDP. The 255HX has an unlocked multiplier, whereas the 251E does not. The 251E has a launch MSRP of $384; no launch MSRP is recorded for the 255HX. Both processors were released on the same date according to the database.
Head-to-Head Benchmarks
The database records benchmark results only for the Intel Core Ultra 7 255HX; no scores are listed for the Intel Core 7 251E. The analysis below interprets the 255HX scores in absolute terms and against its nearest rivals, since direct head-to-head measurements are absent.
In Cinebench R23, the 255HX scores 32612 in multi-core and 2163 in single-core. The multi-core result indicates strong parallel throughput for a 20-thread mobile chip. Its single-core score of 2163 reflects a high boost clock of 5.20 GHz and efficient per-core cache design. The 251E's higher 5.60 GHz boost may provide a single-core advantage, but no recorded score confirms this.
Cinebench R20 shows 17187 multi-core and 2426 single-core for the 255HX. The single-core score here exceeds the R23 single-core score, which is expected as the workloads scale differently. Cinebench R15 shows 4916 multi-core and 327 single-core, again consistent with the older test version's lighter load.
PassMark results for the 255HX cover several specialized workloads. Data compression scores 515143, which is a very high absolute result. Data encryption scores 39499. Extended instructions score 41247. Floating point math scores 160624, while integer math scores 127126. The multi-thread score is 48234, and the physics score is 2926. Random string sorting scores 62591. The single-thread score is 4562.
The 255HX sits in the 93rd percentile of all CPUs, with an average benchmark score of 62738. Its nearest rival, the AMD Ryzen AI Embedded P185, scores 62839, which is 0.2% higher. The AMD Ryzen AI 9 PRO 465 scores 62498, 0.4% lower. The Intel Core i7-13790F scores 63080, 0.5% higher. The Intel Core Ultra 7 265HX scores 63173, 0.7% higher. The 255HX is essentially within a 1% band of all four rivals, indicating a highly competitive field with no dominant leader.
Without recorded benchmarks for the 251E, the data cannot quantify a win margin between the two processors directly. The 251E's 24 cores and 32 threads suggest strong multi-threaded potential, but the 255HX's smaller 3 nm process and higher memory bandwidth may offset thread count in certain workloads. The 255HX's 93rd percentile ranking shows it performs at a high level relative to the broader CPU market.
The Verdict
The recorded data supports different conclusions for different use contexts. The Intel Core Ultra 7 255HX has a complete benchmark profile and ranks in the 93rd percentile among all CPUs. Its average benchmark score of 62738 places it within 1% of four nearest rivals, including the AMD Ryzen AI Embedded P185 and Intel Core Ultra 7 265HX. This chip is a mobile processor with a 55 W TDP, an unlocked multiplier, and support for DDR5 memory at 102.4 GB/s.
The Intel Core 7 251E has no recorded benchmark scores in the database. Its specifications include 24 cores, 32 threads, a 5.60 GHz boost clock, 36 MB of L3 cache, ECC memory support, and both DDR4 and DDR5 compatibility. It is a desktop chip with a 65 W TDP and a launch MSRP of $384. The 251E targets scenarios that benefit from many threads, error-checked memory, and socket flexibility.
The data indicates the 255HX is the better-documented performer, with verifiable scores across Cinebench and PassMark suites. The 251E remains a specification-driven choice: its larger thread count and ECC support are the clear differentiators, but no measurements confirm its actual performance. Users who require mobile deployment or unlocked overclocking should consider the 255HX. Users who need ECC memory or a desktop form factor should consider the 251E, understanding that its benchmark standing is unverified in the database.
Specification Differences
The two processors differ in several recorded fields. The Intel Core 7 251E has 24 cores and 32 threads, while the Intel Core Ultra 7 255HX has 20 cores and 20 threads. Base clocks are 2.10 GHz for the 251E and 2.40 GHz for the 255HX. Boost clocks are 5.60 GHz and 5.20 GHz respectively. TDP is 65 W for the 251E and 55 W for the 255HX. The 251E uses Intel Socket 1700, while the 255HX uses Intel BGA 2114.
Process technology differs: the 251E uses 10 nm from Intel, while the 255HX uses 3 nm from TSMC. The 255HX has a recorded transistor count of 17,800 million; the 251E has none recorded. Die sizes are 257 mm² for the 251E and 243 mm² for the 255HX. L1 cache is 80 KB per core for the 251E and 192 KB per core for the 255HX. L2 cache is 2 MB per core for the 251E and 3 MB per core for the 255HX. L3 cache is 36 MB shared for the 251E and 30 MB shared for the 255HX.
Memory support: the 251E supports DDR4 and DDR5, while the 255HX supports DDR5 only. Memory bandwidth is 89.6 GB/s for the 251E and 102.4 GB/s for the 255HX. ECC support is present on the 251E and absent on the 255HX. PCIe lanes are 16 for the 251E and 20 for the 255HX, both Gen 5. Integrated graphics are UHD Graphics 770 for the 251E and Arc Xe-LPG Graphics 64EU for the 255HX.
Market segments differ: the 251E is a desktop part, while the 255HX is a mobile part. The 251E has a locked multiplier; the 255HX is unlocked. The 251E has a launch MSRP of $384, while the 255HX has no recorded launch MSRP. Both are listed as Active in production status and share the same release date.
Where Each One Wins
The Intel Core Ultra 7 255HX wins in every measured benchmark category because it is the only chip with recorded scores. Its Cinebench R23 multi-core score of 32612 and single-core score of 2163 provide concrete evidence of strong performance. Its PassMark multi-thread score of 48234 and single-thread score of 4562 reinforce this. The 93rd percentile ranking confirms that, within the database's full CPU population, the 255HX is a high performer.
The 255HX also wins on memory bandwidth, with 102.4 GB/s versus 89.6 GB/s for the 251E. It wins on process node efficiency, using 3 nm from TSMC versus 10 nm from Intel. It has more PCIe lanes (20 versus 16), larger per-core caches, and an unlocked multiplier. These specification advantages favor workloads that are bandwidth-sensitive, cache-sensitive, or overclockable.
The Intel Core 7 251E wins on thread count and core count, with 24 cores and 32 threads versus 20 cores and 20 threads. It has a higher boost clock at 5.60 GHz versus 5.20 GHz. It has more total L3 cache at 36 MB versus 30 MB. It supports ECC memory, which the 255HX does not. It supports DDR4 in addition to DDR5, offering broader memory compatibility. It also has a lower launch MSRP at $384, though no price comparison can be made for the 255HX since no MSRP is recorded.
The use-case split follows these recorded differences. The 255HX is the choice for mobile systems, high bandwidth demands, unlocked overclocking, and verified benchmark performance. The 251E is the choice for desktop builds, ECC memory requirements, high thread-count workloads, and legacy DDR4 support. The database records no direct head-to-head benchmarks, so the performance gap between the two remains an open question.