Comparison of PowerColor Red Devil Radeon RX 6900 XT Ultimate video card vs Gainward GeForce RTX 3080 Phantom video card by specifications and benchmarks. PowerColor Red Devil Radeon RX 6900 XT Ultimate runs at 1.825 GHz base clock speed and has 16 GB of GDDR6 memory, while video card Gainward GeForce RTX 3080 Phantom runs at 1.440 GHz base clock speed and has 10 GB of GDDR6X memory. The TDP of the first video card is 300 W, and the second is 340 W+ 6 %. Compare the table of benchmark results to find out which graphic card is better.