Anadtech ran some tests on Oxide’s Star Swarm demo (video below) that is designed to stress DirectX 12 capabilities to its limit by putting massive workload involving a range of effects and element draw calls on the GPU to test how well it performs under the circumstances. AMD and NVIDIA have also provided the necessary WDDM 2.0 drivers that enable DirectX 12 in Windows 10 Technical Preview. Since DirectX 12 is backward compatible and it works on current DirectX 11 graphics cards, they used a range of existing graphics cards from AMD and NVIDIA.
Star Swarm demo: