Intel Core i5-1240U vs Intel Core i5-2450M vs Intel Core i7-1250U

Intel Core i5-1240U

The Intel Core i5-1240U is a 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 1.1 to 4.4 GHz on the performance cluster and 0.8 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 similar Core i7-1260U, the 1240U offers lower clocked CPU cores, a slower iGPU, but the same "Enterprise" vPro management features.

Performance

Compared to the old 7 Watt Comet Lake-Y series (like the i7-10510Y), the performance should be clearly better thanks to the 10 cores and the improved architecture of the P-cores. Compared to the 15 W U-series (like the similar specified Core i5-1245U) the sustained performance will be clearly limited by the 9 Watt TDP. As always, the performance will also greatly depend on the cooling solution, especially for fanless laptops and tablets.

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 80 of the 96 EUs (Execution Units) operating at up to 0.9 GHz.

The CPU is rated at 9 W base power (TDP, PL1) and 29 W max. Turbo power (PL2) and the whole SoC is manufactured on a 10nm process at Intel, which is known as Intel 7.

Intel Core i5-2450M

The Intel Core i5-2450M is a fast dual core processor that first appeared in Dell laptops in 11/2011. It is based on the Sandy Bridge architecture and offers Hyperthreading to handle 4 threads at once (for a better usage of the pipeline). Compared to the faster Core i7, the i5 offers a smaller last level cache of 3MB. The base clock speed is 2.5 GHz but due to Turbo Boost it can reach 2.8 GHz (2 cores active) and 3.1 GHz (1 core active). Compared to the 2510M, the 2450M does not support VT-d and Trusted Execution functions. However, the integrated gpu offers a higher Turbo Boost clock rate.

Sandy Bridge is the evolutionary successor of the Arrandale architecture. The most noteable improvements is the improved Turbo Boost 2.0 and the integration of the graphics card into the 32nm CPU core. 

The i5-2450M offers an integrated graphics card (Intel HD Graphics 3000) which is clearly faster then the older Intel HD Graphics in the Arrandale CPUs. As the new GPU is included in the CPU, it is also manufactured in 32nm and shares the fast level 3 cache with the CPU cores (using a new ring bus). In the 2435M it is clocked with  650 or 1300MHz (with Turbo Boost).

Furthermore, an improved dual-channel DDR3 memory controller is included on the CPU die that is used by the CPU and GPU part.

Due to the improved architecture and the new Turbo Boost 2.0, the average performance of the Core i5-2450M is higher than a similar clocked Arrandale Core i5. Looking at benchmarks of slower clocked Core i5 CPUs, the i5-2450M should position itself slightly above the old Core i5-620M and is therefore suited even for demanding tasks.

The 35W TDP rating includes the integrated GPU and memory controller.

Intel Core i7-1250U

The Intel Core i7-1250U is a 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 1.1 to 4.7 GHz on the performance cluster and 0.8 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 similar Core i7-1260U, the 1250U only offers "Essentials" vPro management features.

Performance

The average 1250U in our database is in the same league as the Ryzen 5 5500U; the i5-1240U, the i7-1260U and the i7-1265U are found close nearby as well.

Thanks to its decent cooling solution and a long-term CPU power limit of 23 W, the Envy x360 13-bf0013dx is among the fastest laptops built around the 1250U that we know of. It can be at least 30% faster in CPU-bound workloads than the slowest system featuring the same chip in our database, as of August 2023.

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 0.95 GHz.

The CPU is rated at 9 W base power (TDP, PL1) and 29 W max. Turbo power (PL2) and the whole SoC is manufactured on a 10nm process at Intel, which is known as Intel 7.