Comparison of PowerColor Fighter Radeon RX 6600 XT video card vs AMD Radeon RX 6400 - Reference Data video card by specifications and benchmarks. PowerColor Fighter Radeon RX 6600 XT runs at 1.968 GHz base clock speed and has 8 GB of GDDR6 memory, while video card AMD Radeon RX 6400 - Reference Data runs at base clock speed and has 4 GB of GDDR6 memory. The TDP of the first video card is 160 W, and the second is 53 W. Compare the table of benchmark results to find out which graphic card is better.