Comparison of PowerColor Liquid Devil Radeon RX 6900 XT video card vs XFX Speedster MERC 319 Radeon RX 6900 XT Black Gaming V2 video card by specifications and benchmarks. PowerColor Liquid Devil Radeon RX 6900 XT runs at 1.825 GHz base clock speed and has 16 GB of GDDR6 memory, while video card XFX Speedster MERC 319 Radeon RX 6900 XT Black Gaming V2 runs at 1.950 GHz+ 7 % base clock speed and has 16 GB of GDDR6 memory. The TDP of the first video card is 300 W, and the second is 300 W. Compare the table of benchmark results to find out which graphic card is better.