Intel Core i7-3520M vs Intel Core i7-7560U vs Intel Core i7-7820HQ

Intel Core i7-3520M

The Intel Core i7-3520M is the fastest dual-core processor for laptops based on the Ivy Bridge architecture at the time of introduction in Q2 2012. 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 2.9 GHz but can dynamically increase clock rates with Turbo Boost up to 3.4 GHz (for 2 active cores) and 3.6 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 i7-3520M 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 (see benchmarks below).

The integrated Intel HD Graphics 4000 offers 16 Execution Units (EUs) clocked at 650 MHz up to 1250 MHz with Turbo Boost, making it one of the fastest variants.

Just like most other Ivy Bridge dual-cores, the i7-3520M is rated at a TDP of 35 W. Therefore, even smaller laptops can use the Core i7.

Intel Core i7-7560U

The Intel Core i7-7560U 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 2.4-3.8 GHz (two cores up to 3.7 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 i7-7500U, the 7560 does have a higher single-core Turbo of 3.8 GHz (+300 MHz) and a higher dual-core Turbo (+200 MHz). The base frequency is lower (-300 MHz), but 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 2.4-3.8 GHz, the Core i7-7560U 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.

Intel Core i7-7820HQ

The Intel Core i7-7820HQ is a fast quad-core processor for notebooks based on the Kaby Lake architecture and was announced in January 2017. It is the second fastest model of the consumer series at the time of the announcement. Only the i7-7920HQ and Xeon E3-1535M v6 are faster. Besides four cores including Hyper-Threading support running at 2.9 - 3.9 GHz (4 cores up to 3.5 GHz, 2 cores up to 3.7 GHz), the processor is also equipped with the HD Graphics 630 GPU as well as a dual-channel memory controller (DDR3L-1600/DDR4-2400). It is manufactured in a 14nm process with FinFET transistors.

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

Due to the higher clock speeds, the performance of the i7-7820HQ is slightly faster than the old Skylake top model Core i7-6920HQ (2.9 - 3.8 GHz). The performance is sufficient even for very demanding tasks and on par with powerful desktop quad-core processors.

Graphics

The integrated Intel HD Graphics 630 has 24 Execution Units (similar to previous HD Graphics 530) running at 350 - 1100 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.

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 45 Watts, but it can also be reduced to 35 Watts by the notebook manufacturers (cTDP down). This will obviously affect the performance, because the Turbo Boost cannot be maintained for longer periods.