Intel Core Ultra 7 255H vs AMD Ryzen Z2 Extreme

Intel Core Ultra 7 255H

The Intel Core Ultra 7 255H is a mobile high-end CPU for larger notebooks based on the Arrow Lake architecture. It offers 16 cores consisting of 6 fast performance cores (Lion Cove) with up to 5.1 GHz and 8 smaller efficiency cores (Skymont) with up to 4.4 GHz clock speed and two additional "low power" efficiency cores with up to 2.5 GHz (Skymont). The CPU has access to 24 MB of cache and is specified with a TDP of 28 watt (PL1, 115W PL2).

The SoC integrates a small dedicated NPU called AI Boost with 13 TOPS (Int8) and optionally supports vPro Essentials. The integrated memory controller supports up to 192 GB LPDDR5/x-8400 or DDR5-6400 (dual channel). The integrated GPU (iGPU) is an Intel Arc 140T graphics card which offers eight Xe cores with up to 2.25 GHz.

Performance - High End

The Core Ultra 7 is superior to the top model Core Ultra 9 285H as only the maximum Turbo frequency is 200 MHz lower. Due to the improved IPC of the cores (especially the efficiency cores), the CPU should perform slightly below the level of the old Raptor Lake Core Core 9 270H (6 + 8 cores, max 5.8 / 4.1 GHz). This makes the CPU very suitable for demanding tasks such as high-end gaming and content creation.

Chiplet design

Like the desktop and HX chips, the Arrow Lake-H chips are based on individual chiplets that are placed on a 22nm base tile from Intel using Foveros 3D packaging. The CPU part comes from TSMC using the modern N3B (3nm) process. As with HX, the GPU also is produced at TSMC and is manufactured using the N5P process. SoC and I/O Tile are also from TSMC but in the older N6 process.

AMD Ryzen Z2 Extreme

The Ryzen Z2 Extreme is a relatively powerful Strix Point family processor that debuted in early 2025. The hybrid architecture APU has 8 CPU cores onboard (a mix of three Zen 5 and five Zen 5c cores) running at 2.0 to 5.0 GHz, along with the 16 CU RDNA 3.5 Radeon 880M graphics adapter and the 50 TOPS XDNA 2 neural engine. Compared to the similar Ryzen AI 7 PRO 360, the Z2 Extreme does not offer the Ryzen AI NPU.

Architecture and Features

Strix Point family APUs are powered by Zen 5 and Zen 5c microarchitecture cores found in two separate clusters, the latter being a slightly slower, smaller and more energy-efficient version of the former. One of the differences between Zen 5 and Zen 5c is cache size; Zen 5 cores have larger caches to work with.

Either way, mobile Zen 5 implementation is reportedly (ChipsAndCheese) closer to desktop Zen 4 than to desktop Zen 5 due to differing cache sizes, vast differences in AVX-512 throughput and other factors.

Elsewhere, the Ryzen chip supports DDR5-5600 and LPDDR5x-8000 RAM, giving system designers a choice between lower latency and higher throughput respectively. The chip is natively compatible with USB 4 (and therefore Thunderbolt). It has PCIe 4.0 support for a throughput of 1.9 GB/s per lane, just like its 8000 series predecessors did. The integrated XDNA 2 NPU, which is a lot more complex than first-gen XDNA was, delivers up to 50 INT8 TOPS for accelerating various AI workloads.

As is usual for mobile CPUs, the Ryzen 7 AI PRO chip is not user-replaceable as it gets soldered down for good.

Performance

The performance should be similar to the Ryzen AI 7 PRO 360 due to the similar specs, but limited due to TDP and heat restrictions in handhelds.

Graphics

The Radeon 880M is the direct successor to the 780M. It packs several differences under the hood, such as faster caches; its 16 RDNA 3.5 architecture CUs/WGPs (768 unified shaders) run at a currently undisclosed clock speed. With well over 30 fps in both Once Human and The First Descendant (1080p - Low), this AMD iGPU is usually certainly fast enough for a fair bit of casual as well as competitive gaming.

Power consumption

The Z2 Extreme is supposed to have a low-term TDP power target of 28 W, with handheld makers free to set between 15 and 35 W. 

The 4 nm TSMC process that these CPUs are built with makes for above average, as of late 2024, energy efficiency.