Comparison of Sapphire Nitro+ Radeon RX 5700 XT 8G video card vs XFX Speedster MERC 319 Radeon RX 6900 XT Limited Black Gaming video card by specifications and benchmarks. Sapphire Nitro+ Radeon RX 5700 XT 8G runs at 1.770 GHz+ 10 % base clock speed and has 8 GB of GDDR6 memory, while video card XFX Speedster MERC 319 Radeon RX 6900 XT Limited Black Gaming runs at 2.150 GHz+ 18 % base clock speed and has 16 GB of GDDR6 memory. The TDP of the first video card is 265 W+ 18 %, and the second is 300 W. Compare the table of benchmark results to find out which graphic card is better.