Comparison of XFX Radeon RX 5700 XT Thicc II Ultra video card vs ASRock Radeon RX 6800 Phantom Gaming D 16G OC video card by specifications and benchmarks. XFX Radeon RX 5700 XT Thicc II Ultra runs at 1.730 GHz+ 8 % base clock speed and has 8 GB of GDDR6 memory, while video card ASRock Radeon RX 6800 Phantom Gaming D 16G OC runs at 1.850 GHz+ 9 % base clock speed and has 16 GB of GDDR6 memory. The TDP of the first video card is 225 W, and the second is 250 W. Compare the table of benchmark results to find out which graphic card is better.