Intel Core i5 8257U 's Advantages
Lower TDP (15W vs 28W)
AMD Ryzen 5 8640HS 's Advantages
Released 4 years and 5 months late
Better graphics card performance
Higher specification of memory (LPDDR5x-7500 vs DDR4-2400)
Larger memory bandwidth (89.6GB/s vs 37.5GB/s)
Newer PCIe version (4.0 vs 3.0)
Higher base frequency (3.5GHz vs 1.4GHz)
Larger L3 cache size (16MB vs 6MB)