Comparison of PowerColor Radeon RX 6700 XT video card vs Sapphire Radeon RX Vega 56 video card by specifications and benchmarks. PowerColor Radeon RX 6700 XT runs at 2.321 GHz base clock speed and has 12 GB of GDDR6 memory, while video card Sapphire Radeon RX Vega 56 runs at 1.156 GHz base clock speed and has 8 GB of HBM2 memory. The TDP of the first video card is 230 W, and the second is 210 W. Compare the table of benchmark results to find out which graphic card is better.