Intel Core i5-1240P vs Intel Core i5-1235U vs Intel Core i7-1255U

Intel Core i5-1240P

The Intel Core i5-1240P is a mid-range Alder Lake-P family SoC designed for use in ultra-light, ultra-thin (yet actively cooled) laptops. It was announced in early 2022 and it has 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 i5's P-cores are Hyper-Threading-enabled for a total of 16 threads when combined with its E-cores. The clock speeds range from 1.7 GHz to 4.4 GHz for the performance cluster and 1.2 GHz to 3.3 GHz for the efficient cluster. The shortcomings of this processor as compared with the slightly faster Core i5-1250P include the slightly lower iGPU clock speed and the limited vPro feature set ("Essentials" tier only, not allowing for remote device management).

Architecture

The i5 is a continuation of Intel's efforts to use the ARM-developed big.LITTLE technology for its own benefit. A single "little" Alder Lake core is supposed to be 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 Core i5-1240P's CPU cores enjoy access to 12 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 of RAM, for reference. Just like the other 12th Gen Intel Core processors, this Core i5 comes with the 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 (FCBGA1744 socket interface).

Performance

Multi-thread performance is most comparable to the Ryzen 5 5500U, Ryzen 5 5600U and, surprisingly enough, the Core i5-1250P, making the i5-1240P a great processor for most consumers. Content creators and gamers will be better served by an H-class CPU such as the mighty Core i7-12700H, though.

Thanks to its decent cooling solution and a long-term CPU power limit of 40 W, the NUC 12 Pro Kit NUC12WSBi5 is among the fastest systems built around the 1240P that we know of. It can be more than 2 times as fast in CPU-bound workloads as the slowest system featuring the same chip in our database, as of August 2023.

Graphics

The built-in graphics adapter in the form of the 80 EU Iris Xe running at up to 1.3 GHz has seen little change from what was built into certain Tiger Lake-UP3 processors, like an i5-1135G7, which is hardly a downside as this iGPU is loaded with modern features such as AV1 video decoding capability and SUHD 4320p monitor support. You can use up to 4 monitors simultaneously with this GPU, provided the laptop has the outputs required. The Xe isn't a stranger to a bit of casual gaming; that said, your mileage may vary depending on how high the Power Limits are and how capable the cooling solution of a laptop is. Expect something close to NVIDIA's MX250 or in other words, acceptable framerates in most games when playing at 1080p / Low settings. Fast RAM is a prerequisite for decent performance as the Iris Xe has to make do with no dedicated video memory.

Power consumption

The i5's base power consumption (also known as the default TDP value or Power Limit 1) is 28 W; its maximum Turbo power consumption (also known as the PL2) is not supposed to exceed 64 W. The "Minimum Assured" power consumption is fairly high at 20 W. All in all, an active cooling solution is a must for a CPU like this.

This 12th generation Intel chip is built with Intel's fourth-gen 10 nm process marketed as Intel 7 for decent, as of late 2022, energy efficiency. Keep in mind that many 7 nm U-class AMD Ryzen 5000 chips are just as fast, or even faster than the i5 while sipping less juice.

Intel Core i5-1235U

The Intel Core i5-1235U is a mid-range 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 1.3 to 4.4 GHz on the performance cluster and 0.9 to 3.3 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 i5-1245U, the 1235U offers lower base clock speeds 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 1235U in our database is in the same league as the Ryzen 5 PRO 5650U and also, surprisingly enough, the i7-1250U and the i7-1260U, as far as multi-thread benchmark scores are concerned. This is a very respectable result, as of mid 2023.

Thanks to its decent cooling solution and a long-term CPU power limit of 27 W, the Beelink SEi12 is among the fastest systems built around the 1235U that we know of. It can be twice as fast in CPU-bound workloads as 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 80 of the 96 EUs (Execution Units) operating at up to 1.2 GHz.

Power consumption

This ULV processor has a Base power consumption of 15 W (also known as the long-term power limit), with 55 W being its maximum Intel-recommended Turbo power consumption. Both values are too high to allow for passively cooled designs.

Core i5-1235U is manufactured on Intel's fourth-gen 10 nm process marketed as Intel 7 for decent, as of mid-2022, energy efficiency.

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.