The AMD RX 6800 XT is the objective winner of this comparison, securing more total spec victories across the evaluated fields. While the AMD RX 6400 maintains a significant lead in power efficiency with an 82% better TDP, the AMD RX 6800 XT provides a massive hardware advantage in raw processing potential. Its most impactful superiority is found in the shader units, where it offers a 500% increase over the alternative, representing the primary differentiator between these two graphics cards.

Users prioritizing power efficiency and low consumption should select the AMD RX 6400, as its TDP advantage makes it the superior choice for constrained environments. Conversely, those requiring maximum computational throughput should choose the AMD RX 6800 XT. By leveraging its vastly higher shader unit count, the latter is better suited for demanding tasks that rely on extensive parallel processing capabilities rather than the power-sipping profile offered by the former.