The Gigabyte B550 AORUS PRO AC and the Gigabyte B850 GAMING X result in an objective tie, as both motherboards secure an equal number of specification victories. The most impactful advantage for the Gigabyte B550 AORUS PRO AC is its PCIe x1 slot configuration, which offers a 100% improvement over the alternative. Conversely, the Gigabyte B850 GAMING X provides a 100% advantage in maximum memory capacity, representing its most significant lead in the comparison.

Users requiring additional expansion cards should prioritize the Gigabyte B550 AORUS PRO AC for its superior PCIe x1 slot availability. Alternatively, those building systems that demand higher memory density should select the Gigabyte B850 GAMING X to leverage its doubled maximum memory capacity. Because both boards perform equally across the remaining specifications, the final decision depends entirely on whether your specific build prioritizes peripheral expansion or increased system memory support.