Intel Core i5-7500T vs Intel Core i7-3612QM vs Intel Core i7-7660U

Intel Core i5-7500T

The Intel Core i5-7500T is a power efficient desktop quad-core based on the Kaby Lake architecture. It was announced early 2017 and offers four cores and no HyperThreading (only 4 threads). The CPU clocks between 2.7 and 3.3 GHz. The integrated Intel HD Graphics 630 graphics card offers 24 EUs clocked at 350 to 1100 MHz. The TDP is specified at only 35 Watt and therefore even lower than mobile HQ quad cores (45 Watt). Thats why the CPU is also used in some laptops.

Intel Core i7-3612QM

The Intel Core i7-3612QM is a fast quad-core processor for laptops based on the Ivy Bridge architecture. It is the fastest mobile processor rated at 35 Watt (at the time of announcement in mid 2012). Due to Hyperthreading, the four cores can handle up to eight threads in parallel leading to better utilization of the CPU. Each core offers a base speed of 2.1 GHz but can dynamically increase clock rates with Turbo Boost up to 2.8 GHz (for 4 active cores), 3.0 GHz (for 2 active cores) and 3.1 GHz (for 1 active core). Compared to the other quad core CPU, the 3612QM is specified at a TDP of only 35 Watt (similar to the dual-core CPUs). The BGA version (that is directly soldered to the mainboard) supports VT-d virtualization, whereas the rPGA version does not. Both dont support vPro, but otherwise all Ivy Bridge features like AES or VT-x are useable.

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 i7-3612QM is slightly above a similarly clocked Sandy Bridge processor due to the architectural improvements. As a result, overall performance is similar to the Sandy Bridge Core i7-2820QM. Altough the 3612QM has a higher model number than the 3610QM, it offers slower clock rates and therefore performs worse. However, the 3610QM is specified at a much higher TDP of 45 Watt.

The integrated Intel HD Graphics 4000 offers 16 Execution Units (EUs) clocked at 650 MHz up to 1100 MHz with Turbo Boost, making it one of the faster variants.

With a TDP of only 35 Watt, the Core i7-3612QM is the first quad-core CPU from Intel that is specified at the level of the dual-core mobile CPUs. Therefore, even smaller laptops can use the Core i7.

Intel Core i7-7660U

The Intel Core i7-7660U is a fast dual-core SoC for notebooks and Ultrabooks based on the Kaby Lake architecture and was announced in January 2017. The CPU has two processor cores clocked at 2.5-4 GHz (two cores up to 3.8 GHz). The processor can execute up to four threads simultaneously thanks to Hyper Threading. It is also equipped with an Intel Iris Plus Graphics 640 GPU with 64 MB eDRAm, a dual-channel memory controller (DDR4) as well as VP9 and H.265 video decoding as well as encoding. The chip is still manufactured in a 14nm process with FinFET transistors.

Compared to the Core i7-7600U, the 7660 does have a higher single-core Turbo of 4 GHz (+100 MHz), but a lower dual-core Turbo (-100 MHz) and a lower base frequency (-300 MHz). However, the CPU part can also use the 64 MB eDRAM as L5 cache.

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

At 2.5-4 GHz, the Core i7-7660U has a slightly lower frequency (except for the single-core Turbo) compared to the Core i7-7600U, but the CPU part can also use the 64 MB eDRAM, so the performance should be similar.

Graphics

The integrated Intel Iris Plus 640 Graphics is the GT3e model of the Kaby Lake GPU (Intel Gen. 9.5). It has 48 Execution Units running at 300-1050 MHz and the performance is comparable to a GeForce 920MX thanks to fast eDRAM cache. However, there aren't any significant improvements compared to the old Iris Pro 540, so modern games can often not be played smoothly or only at the lowest or medium settings, respectively.

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

Power Consumption

The chip is manufactured in an improved 14nm process with FinFET transistors, which improves the efficiency even further. Intel still specifies the TDP with 15 Watts, which is typical for ULV chips. Depending on the usage scenario, the TDP can vary between 7.5 (cTDP Down) and 25 Watts.