AMD Ryzen 9 6900HS 's Advantages
Better graphics card performance
Higher specification of memory (6400 vs 5200)
Higher base frequency (3.3GHz vs 2.4GHz)
Lower TDP (35W vs 55W)
AMD Ryzen 9 7940HX 's Advantages
Released 2 years late
Larger memory bandwidth (83.2GB/s vs 76.8GB/s)
Newer PCIe version (5.0 vs 4.0)
Larger L3 cache size (64MB vs 16MB)
More modern manufacturing process (5nm vs 6nm)