Intel Core i7-7500U vs Intel Core i7-3540M vs Intel Core i7-7700T

Intel Core i7-7500U

The Intel Core i7-7500U is a dual-core processor of the Kaby Lake architecture. It offers two CPU cores clocked at 2.7 - 3.5 GHz and integrates HyperThreading to work with up to 4 threads at once. The architectural differences are rather small compared to the Skylake generation, therefore the performance per MHz is very similar. The SoC includes a dual channel DDR4 memory controller and Intel HD Graphics 620 graphics card (clocked at 300 - 1050 MHz). It is manufactured in an improved 14nm FinFET process (14nm+) at Intel. Compared to the old Skylake Core i7-6500U (2.5 - 3.1 GHz), the i7-7500U clock speed is up to 400 MHz higher.

Intel Core i7-3540M

The Intel Core i7-3540M is the fastest dual-core processor for laptops based on the Ivy Bridge architecture at the time of introduction in Q1 2013. Due to Hyperthreading, the two cores can handle up to four threads in parallel leading to better utilization of the CPU. Each core offers a base speed of 3.0 GHz but can dynamically increase clock rates with Turbo Boost up to 3.5 GHz (for 2 active cores) and 3.7 GHz (for 1 active core). As its Sandy-Bridge-based predecessor Core i7-2640M, it offers a 4 MB L3-Cache.

Ivy Bridge is an enhanced die shrink of the Sandy Bridge architecture with improvements on both GPU and CPU performance. The CPUs are produced in 22nm (versus 32nm Sandy Bridge CPUs) and are the first to introduce 3D transistors for increased energy efficiency when compared to similarly clocked Sandy Bridge processors. Other new features are integrated PCI Express 3.0 and  DDR3(L)-1600 support.

The performance of the Core i7-3540M is slightly above a similarly clocked Sandy Bridge processor due to the architectural improvements. As a result, overall performance is about 5 - 10 % above the old i7-2640M.

The integrated Intel HD Graphics 4000 offers 16 Execution Units (EUs) clocked at 650 MHz up to 1300 MHz with Turbo Boost, making it one of the fastest variants.

Just like most other Ivy Bridge dual-cores, the i7-3540M is rated at a TDP of 35 W. Therefore, even smaller laptops can use the Core i7.

Intel Core i7-7700T

The Intel Core i7-7700T is a fast quad-core processor for desktops based on the Kaby Lake architecture and was announced in January 2017. It is the top model of the 35 Watt models and significantly slower than the similar named Core i7-7700K. The four Skylake based CPU cores are clocked from 2.9 - 3.8 GHz and support HyperThreading / SMT (8 threads).

Architecture

Intel basically uses the same micro architecture compared to Skylake, so the per-MHz performance does not differ. The manufacturer only reworked the Speed Shift technology for faster dynamic adjustments of voltages and clocks, and the improved 14nm process allows much higher frequencies combined with better efficiency than before.

Performance

The performance of the i7-7700T is slightly faster than the Core i5-7600K with sufficient cooling and TDP settings. Therefore, the CPU is fine to handle even demanding tasks and apps.

Graphics

The integrated Intel HD Graphics 630 has 24 Execution Units (similar to previous HD Graphics 530) running at 350 - 1150 MHz. The performance depends a lot on the memory configuration; it should be comparable to a dedicated Nvidia GeForce 920M in combination with fast DDR4-2133 dual-channel memory.

Contrary to Skylake, Kaby Lake now supports hardware decoding for H.265/HEVC Main 10 with a 10-bit color depth as well as Google's VP9 codec. The dual-core Kaby Lake processors, which were announced in January, should also support HDCP 2.2.