Comparison of PowerColor Radeon RX 6800 Red Devil Limited Edition video card vs Sapphire Radeon RX 6900 XT video card by specifications and benchmarks. PowerColor Radeon RX 6800 Red Devil Limited Edition runs at 1.850 GHz+ 9 % base clock speed and has 16 GB of GDDR6 memory, while video card Sapphire Radeon RX 6900 XT runs at 1.825 GHz base clock speed and has 16 GB of GDDR6 memory. The TDP of the first video card is 250 W, and the second is 300 W. Compare the table of benchmark results to find out which graphic card is better.