Comparison of XFX Speedster MERC308 Radeon RX 6600 XT BLACK Gaming video card vs ASUS ROG Strix Radeon RX Vega 64 OC 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 ASUS ROG Strix Radeon RX Vega 64 OC Gaming runs at 1.298 GHz+ 4 % base clock speed and has 8 GB of HBM2 memory. The TDP of the first video card is 160 W, and the second is 295 W. Compare the table of benchmark results to find out which graphic card is better.