Comparison of Sapphire Radeon RX 6900 XT video card vs GALAX GeForce GTX 1660 Super (1-Click OC) video card by specifications and benchmarks. Sapphire Radeon RX 6900 XT runs at 1.825 GHz base clock speed and has 16 GB of GDDR6 memory, while video card GALAX GeForce GTX 1660 Super (1-Click OC) runs at 1.530 GHz base clock speed and has 6 GB of GDDR6 memory. The TDP of the first video card is 300 W, and the second is 125 W. Compare the table of benchmark results to find out which graphic card is better.