Comparison of GIGABYTE Radeon RX 590 Gaming 8G video card vs Sapphire Nitro+ Radeon RX 6900 XT SE video card by specifications and benchmarks. GIGABYTE Radeon RX 590 Gaming 8G runs at 1.469 GHz base clock speed and has 8 GB of GDDR5 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 225 W, and the second is 363 W+ 21 %. Compare the table of benchmark results to find out which graphic card is better.