Qualcomm Snapdragon 680 Advantages
More modern manufacturing process (6nm vs 7nm)
Released 2 years late
Samsung Exynos 990 Advantages
Better graphics card performance FLOPS (1.126 TFLOPS vs 0.284 TFLOPS )
Larger memory bandwidth (44GB/s vs 17GB/s)
Higher Frequency (2730MHz vs 2400MHz)