Comparison of ASRock Radeon RX 6600 Challenger D video card vs MSI Radeon RX 6600 MECH 2X 8G video card by specs and benchmarks. ASRock Radeon RX 6600 Challenger D runs at 1.626 GHz base clock speed and has 8 GB of GDDR6 memory, while video card MSI Radeon RX 6600 MECH 2X 8G runs at 1.626 GHz base clock speed and has 8 GB of GDDR6 memory. The weight is different, 627 g vs 710 g. The TDP of the first video card is 132 W, and the second is 132 W . Compare the benchmark results to find out which video card is better.