Intel Core i5-8257U vs AMD Ryzen 5 3500U

Intel Core i5-8257U

The Intel Core i5-8257U is a quad-core SoC for notebooks based on the Coffee Lake architecture that was announced in the new entry level MacBook Pro 13 in mid 2019. Compared to its predecessor, the CPU is now a quad-core with Hyperthreading support for the execution of up to 8 threads simultaneously. The base frequency is only 1.4 GHz, but the Turbo goes all the way up to 3.9 GHz. It is also equipped with an Intel Iris Plus Graphics 645 GPU with 128 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 faster Core i7-8557U model with eDRAM and 15 Watts, the i5-8257U only features 6 MB smart cache and the slowest clock of the Iris Plus GPU.

Architecture

Intel basically uses the same micro architecture compared to Kaby Lake, 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

Thanks to the relative high Turbo Boost clock, the single thread performance should be very good, but still behind the faster i7 model. The short burst all core performance is clearly better compared to the old dual core predecessors thanks to the additional cores. In sustained workloads, the performance is usually limited by the TDP and cooling. In these workloads the difference to the Core i7 should be also smaller.

Graphics

The integrated Intel Iris Plus 645 Graphics is the GT3e model of the Coffee Lake GPU (Intel Gen. 9.5). It has 48 Execution Units running at 300-1050 MHz and the performance is comparable to a GeForce 930M or 940MX thanks to fast eDRAM cache. However, there aren't any significant improvements compared to the old Iris Plus 650, 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 specifies the TDP with 15 Watts and therefore suited for thin and light laptops.

AMD Ryzen 5 3500U

The AMD Ryzen 5 3500U is a mobile SoC that was announced in January 2019. It combines four Zen+ cores (8 threads) clocked at 2.1 GHz to 3.7 GHz with a Radeon RX Vega 8 iGPU with 8 CUs (512 Shaders) clocked at up to 1200 MHz. Specified at 15 Watt TDP, the SoC is intended for thin mid-range laptops. In Chromebooks, AMD calles the APU AMD Ryzen 5 3500C, but the specifications (and performance) are the same.

The Picasso SoC uses the Zen+ microarchitecture with slight improvements that should lead to a 3% IPS (performance per clock) improvements. Furthermore, the 12 nm process allows for higher clocks at similar power consumption.

The integrated dual-channel memory controller supports up to DDR4-2400 memory. As the features of the Picasso APUs are the same compared to the Raven Ridge predecessors, we point to our Raven Ridge launch article.

Performance

The average 3500U in our database matches the Intel Core i7-1065G7 in multi-thread performance to be an OK lower mid-range option, as of early 2021.

The Honor MagicBook 14 is among the fastest laptops powered by the 3500U that we know of. It can be up to 50% faster in CPU-bound workloads than the slowest system featuring the same chip in our database, as of August 2023.

Power consumption

This Ryzen 5 series chip has a default TDP (also known as the long-term power limit) of 15 W, a value that laptop makers are free to set to anything between 12 W and 35 W with clock speeds and performance changing accordingly as a result. Either way, this is a tad too high to allow for passively cooled designs.

The chip is manufactured on a 12 nm process for subpar, as of late 2022, energy efficiency.