Intel Core i7-4578U vs Intel Core i7-7700 vs Intel Core i5-7Y57

Intel Core i7-4578U

Intel Core i7-7700

The Intel Core i7-7700 is a fast quad-core processor for desktops based on the Kaby Lake architecture and was announced in January 2017. It is the top model of the 65 Watt consumer Kaby-Lake-H series at the time of the announcement. The faster CPUs, like the Core i7-7700K, are specified with 91 Watt. Besides four cores including Hyper-Threading (8 threads) support running at 3.6 - 4.2 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.

Power Consumption

The chip is manufactured in an improved 14nm process with FinFET transistors, which improves the efficiency slightly.

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.