Intel Core i7-7660U vs Intel Core i9-9880H

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.

Intel Core i9-9880H

The Intel Core i9-9880H is a high-end processor for laptops with eight cores based on the Coffee Lake architecture (2019 refresh, CFL-HR). The processor clocks at between 2.3 - 4.8 GHz (4.1 GHz with 8 cores) and can execute up to sixteen threads simultaneously thanks to Hyper-Threading. The 4.8 GHz can only be reached using the "Thermal Velocity Boost" which allows one core to boost to 4.8 GHz (+200 MHz) as long as the CPU temperature is below 50°C. Multiple cores can be boosted +100 MHz below 50°C (not verified). Compared to the predecessor, the Core i9-8950HK, the 9980H is based on the same architecture but offers 2 more cores.

According to Intel, the CPU is manufactured in an improved 14nm (14nm++) process. The i9-8950HK is the fastest model of the Coffee-Lake-H series at the time of announcement and offers an unlocked multiplier for overclocking of the CPU.

The Coffee Lake architecture is similar to Kaby Lake and differs only in the amount of cores (now six cores for the high end versions) and the improved 14nm process (14nm++ according to Intel).

Performance

Due to the two additional cores, performance has increased by almost 33% compared to a similar clocked predecessor and even up to 100% compared to older Kaby-Lake quad-cores. Single thread performance however only improved slightly and the multi-core performance is heavily depending on the cooling.

Graphics

The integrated Intel UHD Graphics 630 iGPU is supposed to offer a slightly higher performance as its clock rate has been increased by 50 MHz. The architecture is identical to that of the Intel HD Graphics 630. We do expect a performance improvement, but as a low-end solution it will probably only display current games smoothly at reduced details - if at all.

Power Consumption

Intel specifies the TDP with 45 watts and therefore the i9 is only suited for big laptops with good cooling solutions.