Intel Core i7-8550U vs Intel Core i5-7Y57

Intel Core i7-8550U

The Intel Core i7-8550U 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 predecessors Core i7-7500U and i5-7260U, respectively, which were still dual-cores, the i7-8550U is equipped with four cores but at a lower base frequency of 1.8 GHz. The Turbo Boost is not specified yet, but should be at least 3.7 - 4 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.

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 i7-8550U depends on the cooling solution of the laptop and the defined TDP limits for short and long term performance. This leads to big differences in our benchmark scores ranging from the 15 Watt reference by Intel up to the 23% higher score of the Inspiron 17-7773 in the Cinebench R15 Multi benchmark. Especially when taxing the CPU for longer periods, these differences can be even higher.

In our usual benchmarks, the average i7-8550U is as fast as the 35 Watt rated Core i5-7440HQ. For single thread performance, the high Turbo Boost frequency helps achieving one of the highest scores for mobile CPUs.

Graphics

The integrated Intel UHD Graphics 620 (Intel Gen 9.5) is untouched from the 8th Gen Kaby Lake chips. With fast dual-channel memory it can reach the performance of a dedicated GeForce 920M.

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 (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.

Intel Core i5-7Y57

The Intel Core i5-7Y57 is a very efficient dual-core SoC for tablets and passively cooled notebooks based on the Kaby Lake architecture and was announced in the Q1/2017. It is a slightly faster version of the Core i5-7Y54 (1.2-3.2 GHz). The CPU consists of two processor cores clocked at 1.2-3.3 GHz (2-core Turbo 2.9 GHz). Thanks to Hyper Threading, the processor can execute up to four threads simultaneously. The chips also includes the Intel HD Graphics 615 GPU, a dual-channel memory controller (DDR3L/LPDDR3) as well as VP9 and H.265 video de- and encoder. It is still produced in a 14 nm process with FinFET transistors. 

Architecture

Intel basically used the familiar micro architecture from the Skylake generation, so the per-MHz performance is identical. Only the Speed-Shift technology for faster dynamic adjustments of the voltages and clocks was improved, and the matured 14 nm process now also enables much higher frequencies and better efficiency than before. 

Performance

Despite the changed designation, the Core i5-7Y57 is the successor to the Core m5-6Y57 (Skylake Y-series), so the chip does not reach the performance level of other Core i processors due to the lower TDP. Thanks to its high Turbo clock, the 7Y57 can sometimes keep up with the 15 Watt models for short peak load and single-thread scenarios, but the clocks will drop significantly under sustained workloads. The CPU is still suitable for many more demanding applications as well as multitasking. 

Graphics

The integrated Intel HD Graphics 615 GPU has 24 Execution Units (EUs) like the old HD Graphics 515 and runs with clocks between 300 and 950 MHz in combination with this processor. The performance heavily depends on the TDP limit as well as the memory configuration; with fast LPDDR3-1866 RAM in dual-channel mode, the GPU should sometimes be able to compete with the HD Graphics 520, but can also be much slower in other scenarios. Modern games from 2016 will, if at all, only run smoothly in the lowest settings.

Contrary to Skylake, Kaby Lake now also supports hardware decoding for H.265/HEVC Main10 with a 10-bit color depth as well as Google's VP9 codec.

Power Consumption

The chip is manufactured in an improved 14 nm process with FinFET transistors, so the power efficiency was once again improved significantly. The typical TDP for the Y-series is specified at 4.5 Watts, and can be adjusted in both directions depending on the usage scenario.