Intel Core i7-1355U vs Intel Core i5-6600T

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 i5-6600T

The Intel Core i5-6600T is a frugal quad-core desktop processor based on the Skylake architecture, which was announced in August 2015. The CPU, which is manufactured in a 14 nm process, runs at 2.7-3.5 GHz and does not support Hyperthreading (only 4 threads simultaneously).

Architecture

Intel uses Skylake to replace both Broadwell as well as Haswell and therefore uses one core design for all TDP classes between 4.5-45 Watts. Several improvements of the Skylake architecture include bigger Out-to-Order-Buffer, optimizations for pre-fetching as well as bigger gains by Hyperthreading. However, the changes are small for a "Tock" – a new micro architecture – in general, so the per-MHz performance is only between 5-10 % (compared to Haswell) or less than 5 % higher (compared to Broadwell), respectively.

Performance

The performance should be similar to the old Core i5-2500K desktop processor (but at a much lower TDP) as well as the mobile Core i5-6440HQ (100 MHz lower base clock and GPU Turbo clock, 10 Watts higher TDP).

Graphics

Graphics are handled by the integrated Intel HD Graphics 530 with 24 EUs (Execution Units), which is clocked at 350 - 1150 MHz. Compared to the HD Graphics 4600 (Haswell, 20 EUs), the performance is increased by around 25 percent. The overall GPU performance is still low-end, so modern games can, if at all, only be played smoothly with low settings.

Power Consumption

Intel specifies the TDP with 35 Watts, so it can also be used in notebooks (although bigger ones).