Intel Core i7-1355U vs Intel Core i5-1235U vs Intel Core i3-1215U

Intel Core i7-1355U

The Intel Core i7-1355U is a high-end mobile CPU for thin and light laptops based on the Alder Lake architecture (Raptor Lake-U / RPL-U series). It was announced in early 2023 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 5 GHz on the performance cluster and 1.2 to 3.7 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 CPU supports "Essentials" 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 high clock speed, the Core i7-1355U should perform slightly better than the older core i7-1265U (up to 4.8 GHz). The faster i7 like the i7-1365U models offer only higher clock rates (and a faster iGPU).

Architecture

The integrated memory controller supports various memory types up to LPDDR5-6400. 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 still only supports PCIe 4.0 x8 for a GPU and two PCIe 4.0 x4 for SSDs.

The integrated graphics card is based on the Xe-architecture and offers all 96 EUs (Execution Units) operating at up to 1.3 GHz.

Power consumption

This Core i7 CPU is rated at a TDP of 15W (base power, PL1) and a maximum turbo power of 55W (PL2). The RPL-U processors are built in a further improved Intel 7 process (10nm SuperFin) that allows higher clock rates.

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 i3-1215U

The Intel Core i3-1215U 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 4 efficient cores (E-cores, Gracemont architecture). The P-cores support Hyper-Threading leading to 8 supported threads when combined with the E-cores. The clock rate ranges from 1.2 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 10 MB L3-cache. Compared to the faster i5 and i7 models, the i3 does not include vPro features.

Performance

The average 1215U in our database is in the same league as the Ryzen 3 5300U and also the Core i7-1185G7, as far as multi-thread benchmark scores are concerned. This is decent enough of a result, as of late 2022. For an entry-level CPU, that is.

Your mileage may vary depending on how competent the cooling solution of your laptop is, and how high the CPU power limits are.

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 card is based on the Xe-architecture and offers 64 of the 96 EUs (Execution Units) operating at up to 1.1 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 in a 10nm process at Intel, which is known as Intel 7.