Intel Core Ultra 9 285 vs Intel Core Ultra X9 388H Comparison

FAQ

Q: Which processor has more physical cores?

A: The Intel Core Ultra 9 285 has 24 cores, while the Intel Core Ultra X9 388H has 16 cores.

Q: What is the average benchmark score difference between the two?

A: The Intel Core Ultra 9 285 records an average benchmark score of 75,488, while the Intel Core Ultra X9 388H posts 44,466. The desktop chip sits at the 95th percentile of all CPUs, compared to the 88th percentile for the mobile part.

Q: Which processor has the higher boost clock?

A: The Intel Core Ultra 9 285 boosts to 5.60 GHz, exceeding the 5.10 GHz peak of the Intel Core Ultra X9 388H.

Q: Do both processors use the same process node?

A: Both use a 3 nm process, but the Intel Core Ultra 9 285 is fabricated by TSMC, while the Intel Core Ultra X9 388H is fabricated by Intel.

Q: Which chip supports ECC memory?

A: The Intel Core Ultra 9 285 supports ECC memory. The Intel Core Ultra X9 388H does not.

Q: What is the shared L3 cache capacity on each processor?

A: The Intel Core Ultra 9 285 has 36 MB of shared L3 cache, while the Intel Core Ultra X9 388H has 18 MB.

Architecture Differences

The Intel Core Ultra 9 285 and the Intel Core Ultra X9 388H represent two distinct design points within Intel's product stack. The 285 belongs to the Core Ultra Series 2 and uses the Arrow Lake architecture with the Arrow Lake-S codename. The 388H is part of the Core Ultra Series 3, built on the Panther Lake architecture with the Panther Lake codename. These are not incremental revisions of the same silicon; they are separate architectures targeting different market segments.

The desktop part, the 285, implements a 24-core, 24-thread configuration with no hyperthreading. The mobile part, the 388H, uses 16 cores and 16 threads. Both chips share a per-core L1 cache of 192 KB and a per-core L2 cache of 3 MB. The shared L3 cache differs substantially, with the 285 providing 36 MB versus 18 MB on the 388H.

Both processors are built on a 3 nm process node, but the foundry differs. The 285 is manufactured by TSMC, while the 388H is manufactured by Intel. The 285 carries a transistor count of 17,800 million on a 243 mm² die. The database does not record transistor or die size data for the 388H.

Memory support diverges clearly. The 285 uses DDR5 memory over a dual-channel bus with a recorded bandwidth of 102.4 GB/s. The 388H uses LPDDR5X memory, also dual-channel, but with a higher recorded bandwidth of 153.6 GB/s. ECC memory is supported on the 285 but not on the 388H.

PCI Express connectivity also differs. The 285 provides Gen 5 with 20 lanes from the CPU. The 388H provides Gen 5 with 4 lanes from the CPU. The integrated graphics are different as well: the 285 uses Arc Xe-LPG Graphics with 64 execution units, while the 388H uses Arc B390.

The socket and form factor separate the two completely. The 285 mounts in Intel Socket 1851 and is a desktop part. The 388H uses Intel BGA 2540 and is a mobile processor. The production status for both is Active. The 285 was released in late 2024, and the 388H in early 2026. Neither processor has an unlocked multiplier.

Where Each One Wins

The benchmark data shows a one-sided comparison. The Intel Core Ultra 9 285 wins all 17 recorded head-to-head tests. The Intel Core Ultra X9 388H records zero wins. The analysis therefore focuses on the magnitude and nature of each victory rather than a split of workloads.

The largest advantages for the 285 come in heavily multithreaded and single-core rendering tests. In Cinebench R23 multi-core, the 285 scores 48,945 against 18,911 for the 388H, a 158.8% lead. The single-core result in the same test is even more lopsided: 6,909 versus 2,200.5, a 214% advantage. These results indicate that the 285 delivers far higher per-thread performance and far higher aggregate throughput.

Integer and floating-point math workloads show consistent dominance. The 285 leads by 81.4% in PassMark integer math and by 73.2% in floating-point math. Data compression and encryption tests also favor the desktop chip, with leads of 66.4% and 64.8% respectively. The 285 also wins in extended instruction workloads by 51.5%.

The narrowest margins appear in tests that are less sensitive to core count. PassMark physics shows only an 11.5% lead for the 285. PassMark single-thread performance shows a 14% lead. Prime number finding shows a 28.2% lead. These smaller gaps still favor the 285, but they indicate that the 388H is comparatively closer in lightly threaded integer work.

The 388H does have a notable advantage in memory bandwidth. The database records 153.6 GB/s for the mobile chip versus 102.4 GB/s for the desktop chip. That advantage does not translate into benchmark wins in the recorded tests, but it does position the 388H as a capable mobile processor for bandwidth-sensitive tasks.

Specification Differences

The two processors differ across nearly every major specification field.

Core and thread counts: the 285 has 24 cores and 24 threads. The 388H has 16 cores and 16 threads.

Clock speeds: the 285 runs at 2.50 GHz base and 5.60 GHz boost. The 388H runs at 2.10 GHz base and 5.10 GHz boost.

Thermal design power: the 285 is rated at 65 watts, while the 388H is rated at 25 watts. This reflects the mobile versus desktop positioning.

Socket: the 285 uses Intel Socket 1851. The 388H uses Intel BGA 2540.

Architecture and codename: the 285 uses Arrow Lake with the Arrow Lake-S codename. The 388H uses Panther Lake with the same codename.

Foundry: the 285 is fabricated by TSMC. The 388H is fabricated by Intel.

Transistor count and die size: the 285 has 17,800 million transistors on a 243 mm² die. No data is recorded for the 388H on either field.

Cache: L1 and L2 are identical at 192 KB per core and 3 MB per core. L3 differs: 36 MB shared on the 285 versus 18 MB shared on the 388H.

Memory support: the 285 uses DDR5. The 388H uses LPDDR5X. Both use dual-channel buses. Memory bandwidth is 102.4 GB/s for the 285 and 153.6 GB/s for the 388H.

ECC memory: supported on the 285, not supported on the 388H.

PCIe lanes: the 285 provides Gen 5 with 20 lanes. The 388H provides Gen 5 with 4 lanes.

Integrated graphics: the 285 uses Arc Xe-LPG Graphics with 64 execution units. The 388H uses Arc B390.

Market segment: the 285 is Desktop. The 388H is Mobile.

Release date: the 285 launched in late December 2024. The 388H launched in early January 2026. The 285 has a launch MSRP of $579. The 388H has no recorded launch MSRP.

Part numbers: the 285 is SRQD4. The 388H is SA4QWQ9EK.

Head-to-Head Benchmarks

The recorded data covers 17 benchmark comparisons, and the Intel Core Ultra 9 285 wins every one. The average benchmark score for the 285 is 75,488, which places it at the 95th percentile of all CPUs. The 388H averages 44,466, placing it at the 88th percentile. The nearest rivals for the 285 are server and desktop parts: the AMD EPYC 8224P at 75,582, the AMD Ryzen 7 PRO 9755X3D at 75,716, and the AMD Ryzen 7 PRO 9755 at 75,738. The 285 trails these by 0.1% to 0.3%. The 388H sits among mobile and desktop mid-range parts: the AMD Ryzen 5 7500X3D at 44,573, the Intel Core i9-13950HX at 44,342, and the AMD Ryzen AI Max 385 at 44,309. The 388H leads these by 0.2% to 0.5%.

The single largest win for the 285 comes in Cinebench R23 single-core, where it scores 6,909 against 2,200.5 for the 388H, a 214% advantage. This is an enormous per-thread gap. The R23 multi-core result shows a 158.8% lead with scores of 48,945 versus 18,911. Cinebench R15 single-core also shows a triple-digit margin at 124.9%, with scores of 696 versus 309.5.

In Cinebench R20, the 285 leads by 56.9% in both multi-core and single-core. The multi-core scores are 20,556 versus 13,101, and the single-core scores are 2,901 versus 1,849. Cinebench R15 multi-core shows a 66.9% lead, with 4,933 versus 2,955.

PassMark integer math delivers one of the larger margins: 164,869 versus 90,882, an 81.4% lead. Floating-point math follows with 194,988 versus 112,550, a 73.2% lead. Random string sorting shows a 67.4% advantage, with 73,651 versus 44,010. Data compression shows 602,121 versus 361,763, a 66.4% lead. Data encryption shows 46,949 versus 28,490, a 64.8% lead. Extended instructions show 45,357 versus 29,943, a 51.5% lead. PassMark multithread shows 56,602 versus 36,811, a 53.8% lead.

The narrowest margins appear in PassMark physics, where the 285 scores 3,598 versus 3,226, an 11.5% lead. PassMark single-thread shows 4,881 versus 4,280, a 14% lead. Prime number finding shows 459 versus 358, a 28.2% lead.

The data indicates that the 285 is the stronger processor in every measured workload. The 388H, despite its higher memory bandwidth and lower power envelope, cannot match the desktop part in any recorded benchmark. The 285 also carries significantly higher core and thread counts, which explains much of the multi-core advantage, but the single-core results show that the architectural advantage is not solely a matter of core count. The 285 leads by over 200% in single-core Cinebench R23, a result that points to a fundamental difference in per-thread execution efficiency between the two designs.