AMD Ryzen 7 8840U 's Advantages
Released 11 months late
Better graphics card performance
Higher specification of memory (LPDDR5x-7500 vs DDR5-5200)
Larger memory bandwidth (89.6GB/s vs 83.2GB/s)
Lower TDP (15W vs 45W)
AMD Ryzen 7 7745HX 's Advantages
Newer PCIe version (5.0 vs 4.0)
Higher base frequency (3.6GHz vs 3.3GHz)
Larger L3 cache size (32MB vs 16MB)