Comparison of XFX Speedster MERC 319 Radeon RX 6800 Black Gaming video card vs Sapphire Nitro+ Radeon RX 6900 XT SE video card by specifications and benchmarks. XFX Speedster MERC 319 Radeon RX 6800 Black Gaming runs at 1.850 GHz+ 9 % base clock speed and has 16 GB of GDDR6 memory, while video card Sapphire Nitro+ Radeon RX 6900 XT SE runs at 1.825 GHz base clock speed and has 16 GB of GDDR6 memory. The TDP of the first video card is 250 W, and the second is 363 W+ 21 %. Compare the table of benchmark results to find out which graphic card is better.