Comparison of Sapphire Radeon RX 5700 XT 8G video card vs ASRock Radeon RX 6600 Challenger D video card by specifications and benchmarks. Sapphire Radeon RX 5700 XT 8G runs at 1.605 GHz base clock speed and has 8 GB of GDDR6 memory, while video card ASRock Radeon RX 6600 Challenger D runs at 1.626 GHz base clock speed and has 8 GB of GDDR6 memory. The TDP of the first video card is 225 W, and the second is 132 W. Compare the table of benchmark results to find out which graphic card is better.