Comparison of XFX Speedster MERC 319 Radeon RX 6900 XT Black Gaming video card vs EVGA GeForce GTX 1660 Ti XC BLACK GAMING video card by specifications and benchmarks. XFX Speedster MERC 319 Radeon RX 6900 XT Black Gaming runs at 1.950 GHz+ 7 % base clock speed and has 16 GB of GDDR6 memory, while video card EVGA GeForce GTX 1660 Ti XC BLACK GAMING runs at 1.500 GHz base clock speed and has 6 GB of GDDR6 memory. The TDP of the first video card is 300 W, and the second is 120 W. Compare the table of benchmark results to find out which graphic card is better.