Comparison of XFX Speedster MERC308 Radeon RX 6600 XT BLACK Gaming video card vs EVGA GeForce GTX 1660 SUPER BLACK GAMING video card by specifications and benchmarks. XFX Speedster MERC308 Radeon RX 6600 XT BLACK Gaming runs at 2.188 GHz+ 11 % base clock speed and has 8 GB of GDDR6 memory, while video card EVGA GeForce GTX 1660 SUPER BLACK GAMING runs at 1.530 GHz base clock speed and has 6 GB of GDDR6 memory. The TDP of the first video card is 160 W, and the second is 125 W. Compare the table of benchmark results to find out which graphic card is better.