Intel Core i7-1255U vs Intel Core i7-1260P vs Intel Core i7-1265U

Intel Core i7-1255U

The Intel Core i7-1255U is a high-end mobile CPU for thin and light laptops based on the Alder Lake architecture. It was announced in early 2022 and offers 2  performance cores (P-cores, Golden Cove architecture) and 8 efficient cores (E-cores, Gracemont architecture). The P-cores support Hyper-Threading leading to 12 supported threads when combined with the E-cores. The clock rate ranges from 1.7 to 4.7 GHz on the performance cluster and 1.2 to 3.5 GHz on the efficient cluster. The performance of the E-cores should be similar to old Skylake cores (compare to the Core i7-6700HQ). All cores can use up to 12 MB L3 cache. Compared to the i7-1265U (fastest U-series CPU at launch), the 1255 offers 100 MHz lower clocked CPU cores and only "Essentials" vPro management features. Compared to the P-series (28W) or H-series (45W), the 15W TDP may limit the sustained performance.

Performance

The average 1255U in our database is in the same league as the Ryzen 5 5600U, as far as multi-thread benchmark scores are concerned. Which is nothing to be ashamed of, as of mid 2023.

Thanks to its decent cooling solution and a long-term CPU power limit of 28 W, the Spectre x360 13.5 14t-ef000 is among the fastest laptops built around the 1255U that we know of. It can be 20% faster in CPU-bound workloads than the slowest system featuring the same chip in our database, as of August 2023.

Architecture

The integrated memory controller supports various memory types up to DDR5-4800, DDR4-3200, LPDDR5-5200, and LPDDR4x-4267. The Thread Director (in hardware) can support the operating system to decide which thread to use on the performance or efficient cores for the best performance. For AI tasks, the CPU also integrates GNA 3.0 and DL Boost (via AVX2). Quick Sync in version 8 is the same as in the Rocket Lake CPUs and supports MPEG-2, AVC, VC-1 decode, JPEG, VP8 decode, VP9, HEVC, and AV1 decode in hardware. The CPU only supports PCIe 4.0 (x8 for a GPU and two x4 for SSDs).

The integrated graphics card is based on the Xe-architecture and offers all 96 EUs (Execution Units) operating at up to 1.25 GHz.

Power consumption

This Core i7 has a "minimum assured" power consumption of 12 W. Its Base power consumption sits at 15 W and its maximum Intel-recommended Turbo power consumption isn't supposed to exceed 55 W. All those values are too high to allow for pasisvely cooled designs.

Last but not the least, Core i7-1255U is built with Intel's fourth-gen 10 nm process marketed as Intel 7 for decent, as of late 2022, energy efficiency.

Intel Core i7-1260P

The Intel Core i7-1260P is an upper mid-range 28 W Alder Lake CPU designed for use in ultra-light laptops. It was announced in early 2022 and it features 4 performance cores as opposed to the 6 cores of the top-of-the-line i7-1280P (P-cores, Golden Cove architecture) mated to 8 efficient cores (E-cores, Gracemont architecture). The P-cores are Hyper-Threading-enabled for a total of 16 threads when combined with the E-cores. The clock speeds range from 2.1 GHz to 4.7 GHz for the performance cluster and 1.5 GHz to 3.4 GHz for the efficient cluster. The i7's shortcomings as compared to Intel Core i7-1270P include the marginally lower clock speeds and limited vPro feature set ("Essentials" tier only, not allowing for remote device management).

Architecture

The i7 is a continuation of Intel's efforts to use the ARM-developed big.LITTLE technology for its own benefit. A single "littile" Alder Lake core is supposed to be just as fast as a Skylake core (as found in the venerable Core i7-6700HQ among other options) which is six years old at this point. All of an Core i7-1260P's CPU cores enjoy access to 18 MB of L3 cache. The integrated memory controller supports various memory types up to LPDDR5-5200, DDR5-4800, LPDDR4x-4267 or DDR4-3200; Intel recommends using no more than 64 GB, for reference. Just like the other 12th Gen Intel Core processors, Intel Core i7-1260P comes with Thread Director which is a new functionality designed to help Windows 11 decide which cores to use for what workload for best performance and efficiency possible. Hardware acceleration of AI algorithms is supported via GNA 3.0 and DL Boost (via AVX2). PCI-Express 5.0 support has not found its way into Alder Lake P processors, so users will have to be content with PCI-Express 4.0 for the time being. Four PCI-Express 4 lanes allow for a read/write rate of up to 7.9 GB/s, provided a suitably fast NVMe SSD is used.

Please note this is not a user-replaceable CPU. It gets soldered permanently on to the motherboard (BGA1744 socket interface).

Performance

Multi-thread performance is most comparable to the Ryzen 7 5800U, Ryzen 7 PRO 5850U and also the Core i5-11260H. This makes the 1260P a great little CPU - one capable of punching above its weight.

Thanks to its decent cooling solution and a long-term CPU power limit of 35 W, the Asus ExpertBook B5 Flip B5602FBN is among the fastest laptops featuring the 1260P that we know of. It can be about 2 times as fast in CPU-bound workloads as the slowest system built around the same chip in our database (as of August 2023).

Graphics

The built-in graphics adapter in the form of the 96 EU Iris Xe running at up to 1.4 GHz has seemingly seen no change from what was built into certain Tiger Lake-UP3 processors, like a i7-1165G7. Which is hardly a downside as this iGPU is loaded with modern features such as AV1 video decoding capability and SUHD 4320p monitor support. Up to 4 monitors can be used simultaneously with this graphics adapter. Its gaming performance is bound to be tied to how high the Power Limits and how good the cooling solution of a laptop are; expect something close to NVIDIA's MX350 or in other words, acceptable framerates in most games when playing at 1080p / Medium settings. Fast RAM is a prerequisite for decent performance as the Iris Xe has to make do with no dedicated video memory. Last but not the least, we discovered that the GPU utilization when playing YouTube UHD 2160p60 videos is higher than it was with Tiger Lake chips.

Power consumption

The i7's base power consumption (also known as the default TDP or Power Limit 1) is 28 W, with 64 W being its maximum Intel-recommended Turbo power consumption (also known as the PL2). Its "Minimum Assured" power consumption sits at 20 W. All in all, an active cooling solution is a must for a CPU like this one here.

The i7-1260P is manufactured on Intel's fourth-gen 10 nm process marketed as Intel 7 for decent, as of late 2022, energy efficiency. Despite that, many 7 nm U-class AMD Ryzen 5000 parts are less power-hungry while being as fast (or even faster, depending on the workload) as the i7.

Intel Core i7-1265U

The Intel Core i7-1265U is a high-end mobile CPU for thin and light laptops based on the Alder Lake architecture. It was announced in early 2022 and offers 2  performance cores (P-cores, Golden Cove architecture) and 8 efficient cores (E-cores, Gracemont architecture). The P-cores support Hyper-Threading leading to 12 supported threads when combined with the E-cores. The clock rate ranges from 1.8 to 4.8 GHz on the performance cluster and 1.3 to 3.6 GHz on the efficient cluster. The performance of the E-cores should be similar to old Skylake cores (compare to the Core i7-6700HQ). All cores can use up to 12 MB L3 cache. The 1265U offers "Enterprise" vPro management features. Compared to the P-series (28W) or H-series (45W), the 15W TDP may limit the sustained performance.

Performance

Thanks to the 10 cores, the multi-threaded performance should be clearly faster than the older quad-core Tiger Lake CPUs with 15 Watt (like the Intel Core i7-1160G7). The sustained performance will be limited by the TDP setting and thermals and therefore only short term loads. Thanks to the architectural improvements of the big Golden Cove cores, the single thread performance should be better than similar clocked Tiger Lake CPUs.

Features

The integrated memory controller supports various memory types up to DDR5-4800, DDR4-3200, LPDDR5-5200, and LPDDR4x-4267. The Thread Director (in hardware) can support the operating system to decide which thread to use on the performance or efficient cores for the best performance. For AI tasks, the CPU also integrates GNA 3.0 and DL Boost (via AVX2). Quick Sync in version 8 is the same as in the Rocket Lake CPUs and supports MPEG-2, AVC, VC-1 decode, JPEG, VP8 decode, VP9, HEVC, and AV1 decode in hardware. The CPU only supports PCIe 4.0 (x8 for a GPU and two x4 for SSDs).

The integrated graphics adapter is based on the Xe-architecture and offers all 96 EUs (Execution Units) operating at up to 1.25 GHz.

The CPU is rated at 15 W base power (TDP, PL1) and 55 W max. Turbo power (PL2) and the whole SoC is manufactured on a 10nm process at Intel, which is known as Intel 7.