The Intel Core i7-8650U is a power efficient quad-core SoC for notebooks and Ultrabooks based on the Kaby Lake Refresh generation and was announced in August 2017. Contrary to its direct predecessor the Core i7-7600U, which were still dual-cores, the i7-8650U is equipped with four cores but at a lower base frequency of 1.9 GHz. The Turbo Boost can go up to 4,2 GHz and therefore also offer good short term single core speeds. The GPU is now named Intel UHD Graphics 620 but otherwise identical to the Intel HD Graphics 620. The integrated memory controller supports DDR4-2400 / LPDDR3-2133 and dual channel memory.
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.
According to Intel, the new quad core models are up to 40% faster than their dual core predecessors. Due to the reduced TDP and the same 14nm+ process, the long term performance and throttling behaviour will be interesting and depending on the laptop design. Therefore, the older 35 Watt quad-core models should be faster in applications that demand longer CPU loads. The performance however is highly depending on the TDP settings and cooling solution of the laptop. Especially, longer loads will show varying results in different laptops.
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.
The chip is manufactured in an improved 14nm process with FinFET transistors (14nm+), the same as the 7th Gen Kaby Lake processors. 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.