Comparison of PowerColor Red Devil Radeon RX 6900 XT Ultimate video card vs KFA2 GeForce GTX 1080 Ti 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 KFA2 GeForce GTX 1080 Ti runs at 1.480 GHz base clock speed and has 11 GB of GDDR5X memory. The TDP of the first video card is 300 W, and the second is 250 W. Compare the table of benchmark results to find out which graphic card is better.