Intel Core Ultra 7 258V vs Intel Core Ultra 7 155U

Intel Core Ultra 7 258V

The Intel Core Ultra 5 258V is an upper mid-range Lunar Lake family processor. This is an SoC for use in tablets and laptops of the slimmer kind that was unveiled in Autumn 2024. It sports 4 new Skymont E-cores and 4 new Lion Cove P-cores running at up to 3.7 GHz and 4.8 GHz respectively, along with the new Arc 140V iGPU and 32 GB of on-package LPDDR5x-8533 RAM. A new 47 TOPS neural engine, Thunderbolt 4 and PCIe 5 SSD support are included as well.

The only difference between this chip and the Ultra 7 256V is the amount of on-package, non-replaceable RAM: 32 GB vs 16 GB respectively.

Architecture and Features

Lunar Lake is built using the Foveros technology (stacking several dies on top of each other and next to each other), just like Meteor Lake was. The new chips make use of the enormous BGA2833 socket interface. Of the 8 cores, not a single one is Hyper-Threading-enabled which is the opposite of what AMD currently does with its Zen 5/5c chips.

Intel claims Lion Cove cores bring a 14% IPC improvement over Redwood Cove. For Skymont and Crestmont, the difference is much higher at 68%. Several tweaks and improvements are present here, such as the Low Latency Fabric that is supposed to make small data transfers between cores/caches a lot faster. The 258V has a very healthy 12 MB of level 3 cache; elsewhere, it has 4 PCIe 5 and 4 PCIe 4 lanes for connecting various kinds of devices, including NVMe SSDs at up to 15.75 GB/s. Thunderbolt 4 support is onboard by default, as is support for CNVi WiFi 7 + BT 5.4 cards from Intel. The 47 TOPS "AI Boost" neural engine is present along with technologies such as Threat Detection to make AI-enabled applications such as the Windows Defender more powerful.

Intel is predicted to get short of on-package RAM in subsequent CPU generations.

Performance

Based on the time we've had with 2 systems powered by the 258V, the chip's multi-thread performance is as good as that of the Core Ultra 7 165U and the Core i7-1360P. Please note that one of the two systems had a higher long-term TDP power target than the Intel-recommended value: 32 W vs 17 W.

Generally speaking, the 288V, 268V, 266V, 258V, 256V are faster than the 238V, 236V, 228V and 226V due to the difference in their last-level cache size (8 MB vs 12 MB) as well as clock speeds. However, the difference in performance between the slowest Lunar Lake chip, the 226V, and the fastest chip, the 288V is fairly small at around 10% to 15%. It depends on the TDP figures of the laptops being pitted against each other more than on anything else.

Graphics

The Arc Graphics 140V is here to replace the Arc 8 iGPU. Its 8 Xe² architecture "cores" run at up to 1,950 MHz and it also has 8 ray tracing units at its disposal. The adapter is DirectX 12 Ultimate-enabled and able to HW-decode a long list of popular video codecs such as h.266 VVC, h.265 HEVC, h.264 AVC, AV1 and VP9. Three SUHD 4320p monitors can be used simultaneously with this iGPU.

All 2023 and 2024 games are playable at 1080p on low graphics settings or higher with this iGPU. We got well over 30 fps in Ghost of Tsushima and almost 40 fps in Baldur's Gate 3. This means the Radeon 780M gets left behind while the Radeon 890M reigns supreme.

Power consumption

This 2nd generation Core Ultra processor is supposed to consume 17 W when under long-term workloads. The Intel-recommended short-term power limit for the chip sits at 37 W.

Intel Core Ultra 7 155U

The Intel Core Ultra 7 155U is a mid-range Meteor Lake chip that debuted in December 2023. This 1st Gen Core Ultra processor has come to replace 13th generation Core processors; it has 12 cores (2 + 8 + 2) and 14 threads at its disposal. Its Performance cores, of which there are 2, are HT-enabled and run at up to 4.8 GHz while its Efficient cores, of which there are 10 (8 main cores plus 2 extra ones found in the Low Power Island) run at up to 3.8 GHz. The 4-core Intel Arc Graphics, just out of the oven, serves as the integrated graphics adapter - this runs at up to 1.95 GHz - and there is a bevy of other brand-new technologies on offer as well such as 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 2.1 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 155U comes with 12 MB of L3 cache which is a significant reduction compared to the 24 MB that the 155H, the 165H and the 185H have. The processor has a decent number of PCIe 4 lanes for NVMe SSD speeds up to 7.8 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 155U features built-in Thunderbolt 4 support and Intel CNVi Wi-Fi support. It is also worth mentioning that Intel chose to keep native SATA III support that AMD had removed from its Ryzen processors quite a while ago.

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

Performance

While we have no way of knowing what the 155U will be like, as of December 2023, it's safe to expect the chip to be almost as fast as the Core i7-1340P (Raptor Lake, 12 cores, 16 threads, up to 4.6 GHz), as far as multi-thread performance is concerned.

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 4-core Arc Graphics runs at up to 1.95 GHz. We expect the iGPU to be about as fast as the aging 96 EU Iris Xe meaning it's good enough for most games, as long as one sticks to 1080p and mostly low quality settings.

A proper DX12 Ultimate graphics adapter, the Arc Graphics 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.

Power consumption

This Core Ultra 7 series processor has a Base power consumption of 15 W, with 57 W being its maximum Intel-recommended Turbo power consumption. An active cooling solution is a must for a system powered by this chip.

The 155U is comprised of several 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.