The ASRock X870E Taichi is the objective winner of this comparison, securing victory in twelve out of fourteen measured specifications. Its most significant technical advantage is its maximum memory capacity, which is 300% higher than that of the alternative. By outperforming the competition across the vast majority of categories, this motherboard establishes itself as the superior option for users prioritizing high-end hardware specifications and expanded system headroom.

Choose the ASRock X870E Taichi if your primary requirement is maximum memory support for demanding workloads. Conversely, the MSI PRO B660M-A WIFI DDR4 is the better selection for users who specifically prioritize expansion, as it offers a 100% advantage in available PCIe x1 slots. Selecting between these two components should depend entirely on whether your build necessitates the significantly higher memory ceiling of the former or the increased slot connectivity of the latter.