Intel Core Ultra 7 255U vs Intel Core Ultra 7 258V

Intel Core Ultra 7 255U

The Intel Core Ultra 7 255U is an upper mid-range CPU with 12 cores from the Arrow Lake U series, which was introduced at the beginning of 2025. The chip is similar to the Meteor Lake U series, but the compute part is manufactured using the modern Intel 3 process and therefore offers higher clock rates.

Like its predecessor, the SoC is based on a tile/chiplet design. The smaller compute tile (compared to the H processors) offers 2 performance cores (P cores, Redwood Cove architecture, SMT) and 8 efficiency cores (E cores, Crestmont architecture). The P-cores support hyperthreading (therefore 14 threads together) and clock up to 5.2 GHz. The E-cores clock at a maximum of 4.2 GHz. In addition, there are now two more low-power efficiency cores with up to 2.4 GHz on the low-power island; the compute tile can therefore be completely deactivated when idle and during simple tasks in order to save power.

Performance

Due to the higher clock rates, the Core Ultra 7 255U can clearly distinguish itself from the old top model Core Ultra 7 165U (12 cores, max 4.9 / 3.8 GHz, 12 MB cache). The old Core Ultra 7 155U lags even further behind due to its low clock rates.

Graphics unit

The Core Ultra 7 155U offers a new Arc-based iGPU called Intel Graphics with 4 Xe cores and 64 EUs that reach a maximum of 2.1 GHz. However, the performance is far below the new Arc iGPU in the H series.

Features

Arrow Lake-U has integrated WiFi 6E (WiFi 7 optional). The integrated memory controller now supports LPDDR5/x-8400 or DDR5-6400 (max. 128 GB). A dedicated NPU (2x Gen3 Neural Compute Engines) is now used. The Xe Media Engine supports MPEG-2, AVC, VC-1 Decode, JPEG, VP8 Decode, VP9, HEVC and AV1 Decode up to 8K 10-bit HDR. The chip now supports PCIe-5.0 (x8 for GPU) and PCIe-4.0 (three x12 for SSDs).

Power consumption

The Intel Core Ultra 7 255U is specified with 15 watts TDP (base) and 57 watts (PL2) max. turbo power. Meteor Lake consists of five individual chips, whereby the processor part is manufactured in the new Intel 3 process (5nm). The graphics unit is produced at TSMC in N5 and the SoC and I/O tile in the older N6 process. These 4 chips are then applied to the 22nm base tile using the Foveros process.

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.