MediaTek Dimensity 900 Advantages
Better graphics card performance FLOPS (0.621 TFLOPS vs 0.416 TFLOPS )
Larger memory bandwidth (18.4GB/s vs 17.07GB/s)
More modern manufacturing process (6nm vs 7nm)
Lower TDP (4W vs 8W)
Released 1 years late
MediaTek Dimensity 820 Advantages
Higher Frequency (2600MHz vs 2400MHz)