Intel Core Ultra 7 255H VS Intel Core Ultra 7 255U

Both the Core Ultra 7 255H and Core Ultra 7 255U are laptop-class processors sharing the same BGA 2049 socket, 3 nm fabrication process, integrated graphics, 64-bit support, and a maximum junction temperature of 110 °C — meaning their fundamental platform design and thermal ceiling are identical.

The most consequential difference in this group is Thermal Design Power: the 255H is rated at 28W while the 255U runs at just 15W. In practice, TDP governs how much sustained power a chip can consume and dissipate. A higher TDP generally allows the processor to maintain higher clock speeds under load for longer, translating to better sustained performance — but it also demands a larger cooling system and draws more from the battery. The 255U's lower TDP makes it the natural fit for thin-and-light ultrabooks prioritizing battery life and fanless or near-silent designs, whereas the 255H targets thicker, better-cooled laptops where performance headroom matters more.

On connectivity, the 255H supports PCIe 5.0 versus the 255U's PCIe 4.0, giving the 255H an edge for pairing with next-generation SSDs or discrete GPUs that can leverage the doubled bandwidth of PCIe 5. Overall, the 255H holds a clear advantage in raw performance potential and I/O bandwidth, while the 255U wins on power efficiency — the right choice depends entirely on whether the target laptop prioritizes performance or portability.

The Intel Core Ultra 7 255H and Intel Core Ultra 7 255U processors differ in several performance-related specifications. The 255H features a CPU speed of 6 cores running at 2 GHz and 8 cores at 1.5 GHz, while the 255U has a CPU speed of 2 cores at 2 GHz and 8 cores at 1.7 GHz. This means the 255U has a slightly higher base clock speed on its lower-performance cores.

In terms of CPU threads, the 255H supports 16 threads, whereas the 255U has 14 threads, indicating the 255H is slightly better equipped for handling multi-threaded tasks. Both processors are capable of reaching high turbo clock speeds, with the 255H boosting to 5.1 GHz and the 255U reaching a slightly higher 5.2 GHz.

Both processors feature an unlocked multiplier and utilize big.LITTLE technology, though the clock multiplier is the same at 20 for both models, which means neither product has a distinct advantage in this regard.

The PassMark benchmark results for the Intel Core Ultra 7 255H and Intel Core Ultra 7 255U show a significant performance gap. The 255H has a total PassMark result of 30,756, compared to the 255U's 18,555, indicating the 255H outperforms the 255U by a substantial margin in overall processing power. In single-threaded performance, the 255H scores 4,373, while the 255U scores 3,732, again showing an advantage for the 255H, though the difference is smaller.

Both processors also have overclocked results, with the 255H reaching 30,494 and the 255U reaching 20,473. This shows that the 255H maintains its lead even when overclocked, though the gap narrows slightly in this mode.

Overall, the Intel Core Ultra 7 255H offers stronger benchmark scores across the board, especially in multi-threaded tasks, while the 255U lags behind, particularly in the total PassMark result.

The integrated graphics on the Intel Core Ultra 7 255H and Intel Core Ultra 7 255U share many similarities. Both processors support DirectX 12 Ultimate, OpenGL version 4.6, and OpenCL version 3, ensuring compatibility with modern graphics workloads and applications.

However, the 255H has a slightly higher GPU turbo speed of 2,250 MHz, compared to the 255U's 2,100 MHz. Despite this difference, both processors support up to 4 displays, so there's no difference in their display capabilities.

Overall, the key distinction lies in the GPU turbo speed, with the 255H offering a slightly faster clock, while both processors provide the same high-level graphics support.

Both the Intel Core Ultra 7 255H and Intel Core Ultra 7 255U feature identical memory specifications. They both support a maximum RAM speed of 8,400 MHz and use DDR5 memory. Each processor is equipped with two memory channels and can support up to 128GB of RAM.

Neither processor supports ECC memory, which is typically used for error correction in more specialized systems.

Overall, the memory capabilities are the same for both processors, with no differences in speed, type, channels, maximum capacity, or ECC support.

The Intel Core Ultra 7 255H and Intel Core Ultra 7 255U share many similar features, particularly in their instruction set support. Both processors include MMX, F16C, FMA3, AES, AVX, AVX2, SSE 4.1, and SSE 4.2, which enable them to handle a wide range of multimedia and computational tasks efficiently.

However, there is a key difference between the two in terms of multithreading. The 255H does not support multithreading, while the 255U does. This means the 255U can handle more simultaneous threads, potentially offering better performance for certain workloads that benefit from multithreading.

Both processors also include an NX bit, a security feature that helps prevent malicious code execution, ensuring a similar level of security between the two models.