Intel Core Ultra 5 245K vs Intel Core Ultra X9 378H Comparison

Where Each One Wins

The benchmark split between the Intel Core Ultra 5 245K and the Intel Core Ultra X9 378H is heavily lopsided. The desktop part claims 13 of the 17 recorded head-to-head tests, while the mobile part takes 4. That distribution alone tells the story: the Ultra 5 245K is the general-purpose compute leader, but the X9 378H has specific strengths that matter in certain workloads.

The Ultra 5 245K wins across the PassMark suite in almost every category. Its largest margins come in random string sorting (23.4% ahead), extended instructions (20.1% ahead), and data compression (18.7% ahead). These are throughput-oriented tasks that benefit from sustained multi-core execution and higher memory bandwidth per thread. The desktop chip also leads in floating point math by 14.1%, integer math by 6.4%, and data encryption by 11.5%. In Cinebench R15 multicore, it posts a 17.3% advantage, and in R20 multicore it leads by 12.4%. The passmark multithread score favors the 245K by 12.4% as well.

The X9 378H wins in three Cinebench tests and one PassMark test. Its biggest victory is Cinebench R23 single-core, where it beats the 245K by 53.6%. That is a massive gap. It also wins Cinebench R15 single-core by 30.3%, Cinebench R23 multicore by 23%, and PassMark physics by 9.5%. The R23 multicore win is notable because it contradicts the R15 and R20 multicore results, suggesting the mobile chip scales better under longer, heavier multi-threaded loads despite losing shorter multicore tests.

So the split is clear. The 245K dominates most everyday compute, compression, encryption, and math workloads. The X9 378H wins where single-thread performance and sustained long-duration multicore rendering matter, plus the physics simulation test.

Architecture Differences

The two processors come from different Intel generations and target different market segments. The Ultra 5 245K is a desktop part in the Core Ultra Series 2, built on the Arrow Lake architecture with the codename Arrow Lake-S. It uses the Intel Socket 1851 and is fabricated by TSMC on a 3 nm process. The X9 378H belongs to Core Ultra Series 3, uses the Panther Lake codename with the Panther Lake-H generation label, and is built by Intel on its own 3 nm node. The mobile chip uses Intel BGA 2540.

Core counts differ. The 245K has 14 cores and 14 threads, all physical without hyperthreading. The X9 378H has 16 cores and 16 threads, also without hyperthreading. The desktop part has a higher base clock at 4.20 GHz versus 2.00 GHz, and a higher boost clock at 5.20 GHz versus 5.00 GHz. The TDP figures are far apart: 125 W for the 245K versus 25 W for the X9 378H.

Cache layouts differ. Both have 192 KB of L1 per core, but the 245K has 3 MB of L2 per core while the X9 378H has 2.5 MB. The shared L3 is larger on the desktop chip at 24 MB versus 18 MB. The desktop part carries 17,800 million transistors on a 243 mm² die; the mobile chip has no recorded transistor or die size data.

Memory support diverges. The 245K uses DDR5 with dual-channel support and 102.4 GB/s bandwidth. The X9 378H uses LPDDR5X with dual-channel support and 153.6 GB/s bandwidth, a 50% higher theoretical memory bandwidth figure. The desktop chip supports ECC memory; the mobile chip does not. PCIe lanes also differ: the 245K offers Gen 5 with 20 lanes (CPU only), while the X9 378H offers Gen 5 with only 4 lanes (CPU only).

Integrated graphics differ. The 245K has Arc Xe-LPG Graphics with 64 EU. The X9 378H has Arc B390. The desktop part has an unlocked multiplier and a known part number (SRQCT); the mobile chip is locked and its part number is unknown. The 245K launched on 2024-10-23 with a launch MSRP of $319. The X9 378H released on 2026-04-03 with no launch MSRP recorded.

FAQ

Q: Which processor has more cores?

A: The Intel Core Ultra X9 378H has 16 cores and 16 threads. The Intel Core Ultra 5 245K has 14 cores and 14 threads.

Q: Which chip has the higher boost clock?

A: The Intel Core Ultra 5 245K boosts to 5.20 GHz. The Intel Core Ultra X9 378H boosts to 5.00 GHz.

Q: Does either chip support ECC memory?

A: Yes, the Intel Core Ultra 5 245K supports ECC memory. The Intel Core Ultra X9 378H does not.

Q: Which processor wins in Cinebench R23 single-core?

A: The Intel Core Ultra X9 378H wins by 53.6%, scoring 4595 versus 2132 for the Ultra 5 245K.

Q: Which processor has higher memory bandwidth?

A: The Intel Core Ultra X9 378H has 153.6 GB/s memory bandwidth. The Intel Core Ultra 5 245K has 102.4 GB/s.

Q: Which chip has a larger L3 cache?

A: The Intel Core Ultra 5 245K has 24 MB of shared L3. The Intel Core Ultra X9 378H has 18 MB.

Specification Differences

The two processors differ in nearly every major specification category. The X9 378H has 16 cores versus 14 for the 245K, and 16 threads versus 14. Base clock favors the desktop part at 4.20 GHz versus 2.00 GHz, and boost clock favors it at 5.20 GHz versus 5.00 GHz. TDP is 125 W for the 245K and 25 W for the X9 378H. Socket types are entirely different: Intel Socket 1851 versus Intel BGA 2540.

Architecture and codename differ: Arrow Lake / Arrow Lake-S for the 245K, Panther Lake / Panther Lake-H for the X9 378H. The generation labels are Ultra 5 (Arrow Lake) versus Ultra X9 (Panther Lake-H). Both use a 3 nm process, but the foundry differs: TSMC for the 245K, Intel for the X9 378H. Transistor count and die size are recorded only for the desktop chip: 17,800 million transistors and 243 mm².

Cache sizes differ in L2 and L3. The 245K has 3 MB L2 per core and 24 MB shared L3. The X9 378H has 2.5 MB L2 per core and 18 MB shared L3. L1 is identical at 192 KB per core. Memory support differs: DDR5 for the desktop, LPDDR5X for the mobile. Memory bandwidth is 102.4 GB/s versus 153.6 GB/s. ECC support is present on the 245K, absent on the X9 378H. PCIe lanes are 20 versus 4, both Gen 5. Integrated graphics are Arc Xe-LPG Graphics 64EU versus Arc B390. The 245K has an unlocked multiplier; the X9 378H does not. Release dates differ by over a year: 2024-10-23 versus 2026-04-03. The 245K has a launch MSRP of $319; the X9 378H has none recorded.

Head-to-Head Benchmarks

The largest single victory for the Ultra 5 245K comes in Cinebench R15 multicore, where it scores 3850 against 3281 for the X9 378H, a 17.3% margin. In Cinebench R20 multicore, the 245K scores 15368 versus 13672, a 12.4% lead. The desktop chip also wins Cinebench R20 single-core by 12.4%, scoring 2169 versus 1929.

PassMark results heavily favor the 245K. Random string sorting shows the biggest gap at 23.4% (55098 versus 44648). Extended instructions follow at 20.1% (37617 versus 31315). Data compression is 18.7% ahead (458817 versus 386591). Floating point math is 14.1% ahead (130678 versus 114500). Data encryption is 11.5% ahead (33286 versus 29840). PassMark multithread is 12.4% ahead (43047 versus 38298). Integer math is 6.4% ahead (98524 versus 92603). Find prime numbers is 16% ahead (414 versus 357). PassMark single-thread is 5.9% ahead (4714 versus 4453).

The X9 378H wins its tests by wide margins in some cases. Cinebench R23 single-core is its best result: 4595 versus 2132, a 53.6% advantage. Cinebench R15 single-core shows 462 versus 322, a 30.3% lead. Cinebench R23 multicore favors the mobile chip at 32553 versus 25066, a 23% margin. PassMark physics goes to the X9 378H at 3404 versus 3081, a 9.5% lead.

The contrast between Cinebench R15/R20 multicore results and the R23 multicore result is worth examining. The 245K wins the first two by 17.3% and 12.4%, but loses R23 by 23%. This suggests the X9 378H sustains performance better over the longer R23 workload, or that its higher memory bandwidth (153.6 GB/s versus 102.4 GB/s) helps in that specific test. Similarly, the R23 single-core result at 53.6% is far larger than the R15 single-core gap of 30.3%, indicating the mobile chip's single-thread advantage grows with workload duration.

The average benchmark score in the database places the 245K at 54053 with a 91st percentile ranking. The X9 378H averages 47468 with an 89th percentile ranking. The nearest rivals for the 245K include the Intel Xeon 6505P at 53701 (0.7% behind), the Intel Core i7-14700F at 53620 (0.8% behind), and the AMD Ryzen 9 9900X3D at 54762 (1.3% ahead). The X9 378H sits near the AMD Ryzen 9 PRO 5945 at 47527 (0.1% behind), the Intel Core Ultra 7 265T at 47697 (0.5% ahead), and the Intel Core i9-12900F at 47176 (0.6% behind).

The Verdict

The data supports a straightforward conclusion. The Intel Core Ultra 5 245K is the stronger overall processor in the recorded benchmarks. It wins 13 of 17 tests and holds a higher average benchmark score (54053 versus 47468) and a higher percentile ranking (91 versus 89). Its wins span compression, encryption, math, sorting, and most Cinebench tests. For users running general desktop workloads, multi-threaded productivity, or data processing tasks, the 245K delivers consistently better results.

The Intel Core Ultra X9 378H is not without merit, but its wins are concentrated in specific areas. Its single-core Cinebench results are exceptional, with a 53.6% lead in R23 and a 30.3% lead in R15. It also wins R23 multicore by 23% and PassMark physics by 9.5%. These results indicate that the mobile chip has strong sustained single-thread performance and excels in certain long-running rendering or physics simulation workloads. Its higher memory bandwidth of 153.6 GB/s versus 102.4 GB/s may explain part of the R23 multicore advantage.

The specification differences reinforce the benchmark picture. The X9 378H has more cores (16 versus 14) but a much lower base clock (2.00 GHz versus 4.20 GHz). The 245K has a higher boost clock (5.20 GHz versus 5.00 GHz), a larger L3 cache (24 MB versus 18 MB), more PCIe lanes (20 versus 4), and ECC support. The mobile chip compensates with faster memory bandwidth and a much lower TDP (25 W versus 125 W), which matters for its mobile segment but does not translate into benchmark dominance.

The verdict from the recorded data: the Ultra 5 245K is the pick for desktop compute, multi-threaded throughput, and tasks that rely on the PassMark suite. The Ultra X9 378H is the pick for single-thread-heavy workloads, sustained Cinebench R23 rendering, and physics simulation, where its 53.6% single-core and 23% multicore advantages are decisive. The 91st percentile ranking for the 245K and 89th for the X9 378H place both in the upper tier of all CPUs, but the 245K holds the higher position in the database.