Comparison of PowerColor Red Devil Radeon RX 6900 XT Ultimate video card vs GALAX GeForce RTX 3090 EX Gamer White (1-Click OC) 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 GALAX GeForce RTX 3090 EX Gamer White (1-Click OC) runs at 1.395 GHz base clock speed and has 24 GB of GDDR6X memory. The TDP of the first video card is 300 W, and the second is 420 W+ 20 %. Compare the table of benchmark results to find out which graphic card is better.