Intel Core Ultra 7 255H vs Intel Core Ultra 7 155H

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.

Intel Core Ultra 7 155H

The Intel Core Ultra 7 155H is a high-end laptop processor of the Meteor Lake series that has 16 cores (6 + 8 + 2) and 22 threads at its disposal. This 1st Gen Core Ultra chip has come to replace 13th generation Core chips; its 16 cores are comprised of 6 HT-enabled Performance cores running at up to 4.8 GHz and 10 Efficient cores (8 main cores plus 2 extra ones found in the Low Power Island) running at up to 3.8 GHz.

The 8-core Arc GPU, just out of the oven, serves as the integrated graphics adapter - this runs at up to 2.30 GHz - and there is a bevy of other brand-new technologies on offer as well, including the integrated AI Boost NPU with two Gen 3 engines for hardware AI workload acceleration.

Architecture and Features

With Meteor Lake, Intel intends to deliver higher CPU performance, higher GPU performance and at the same time, longer battery life than what Raptor Lake chips were capable of. The company also wants a large piece of the AI cake and is working with Microsoft and other partners to make that happen. As a result, Windows Defender is now AI-enabled, meaning it can use the Intel NPU to take some of the load off the main CPU cores. We also get this new Intel Device Discovery technology that is designed to give us a better hardware-based remote laptop management than ever before; and, to make things even better, Intel now offers a dedicated Arc Pro graphics driver for workstations.

This generation of Intel Core processors features Redwood architecture P-cores and Crestmont architecture E-cores. Both come with slight architectural improvements over Raptor Cove and Gracemont respectively for slightly higher performance-per-clock figures; the interesting thing is that of the 10 E-cores, two are actually a separate cluster located on what Intel calls a "Low Power Island". Essentially, the latter is an SoC within an SoC that can stay active while most other parts of the chip are temporarily switched off to save power. The low-power E-cores run at up to 2.5 GHz. Intel hopes this approach will let it deliver unprecedentedly low power consumption figures when under low load, boosting battery life of laptops and tablets powered by Meteor Lake.

To build its Meteor Lake processors, Intel uses the Foveros technology (stacking several chips on top of each other). This is a cost-cutting measure more than anything else, as manufacturing several small dies on several different processes is so much cheaper than making a huge single die and hoping that there are no defects in it that will require disabling some parts of it.

Elsewhere, the Core Ultra 7 155H comes with 24 MB of L3 cache and a very healthy number of PCIe 5 and PCIe 4 lanes for NVMe SSD speeds up to 15.7 GB/s. It supports RAM running at up to 7467 MHz (DDR5-5600, LPDDR5-7467, LPDDR5x-7467, to be specific - which is about as good as what 8040 series Ryzen chips have). Naturally, the chip features built-in Thunderbolt 4 support and Intel CNVi Wi-Fi support; fascinatingly enough, Intel chose to keep native SATA III support that AMD had removed from its Ryzen processors quite a while ago.

The 155H is compatible with 64-bit Windows 10, 64-bit Windows 11 and with many Linux distros.

Performance

If one chooses to trust the official performance data published by Intel, then the 155H is about as fast as the Ryzen 9 6900HX (Zen 3 Plus, 8 cores, 16 threads, up to 4.9 GHz), as far as multi-thread performance is concerned. This isn't a ground-breaking result but let's just wait for our in-house testing results instead of jumping to conclusions.

Either way, real-world performance of the chip may vary significantly depending on how high the CPU power limits are and how competent the cooling solution of the system is.

Graphics

The 8-core Arc GPU running at up to 2.30 GHz is slated to be a proper alternative to the mighty Radeon 780M. The thing is almost as fast as the GTX 1650 (Laptop) and the RTX 2050 (Laptop) to represent some seriously solid performance gains over aging Xe-series integrated GPUs. If one chooses to take Intel's word for it, that is.

A proper DX12 Ultimate graphics adapter, the Arc is no stranger to ray tracing and other modern technologies including AI frame generation (XeSS). It will let you connect up to four SUHD 4320p monitors and it will both HW-encode and HW-encode the most widely used video codecs including AVC, HEVC and AV1 in a fast and efficient manner.

Your mileage may vary depending on how high the CPU power limits are, how competent the cooling solution of your system is, how fast the RAM of your system is. The latter is really important; Intel stresses that for the Arc to deliver the best results possible, multi-channel RAM configuration is a must.

Power consumption

This mighty Core Ultra 7 series processor has a Base power consumption of 28 W, while its Turbo power consumption is not supposed to exceed 115 W. Its Base power consumption is supposed to be around 64 W, however, most laptop makers will probably go for a higher value to get higher clock speeds and thus better performance. Either way, a powerful cooling solution will be needed to sort out this chip's hot temper.

The 155H is comprised of five small chips ("tiles") that are connected using Intel's Foveros technology. The tile containing main CPU cores is produced on the fairly modern 7 nm Intel process marketed as Intel 4 while most other tiles (the iGPU, the I/O die, ...) are built with TSMC's N5 and N6 processes. The base tile is built with the old Intel 22FFL process.