Our detail settings are shown below:
Our testbed, in this case, was my own system — an Ivy Bridge-E Core i7-4960X with 16GB of DDR3-1600 installed in a quad-channel configuration.
We picked two separate tests for our evaluation. Our first is a simple circular fly-around of the city of Dalaran. Circling the cities outer perimeter via flying mount takes almost exactly a minute and constitutes a simple test of API performance in non-challenging conditions. Our second test is a five-minute play session in the Seething Shore PvP battleground. The Seething Shore BG went into the game back in February, but it’s the closest thing to Battle for Azeroth content we can currently benchmark (the BG is focused on the collection of Azerite, which also plays a major role in BfA). Obviously, PvP matches can play out differently, which is why we chose a relatively long play-through period to compensate.
It’s possible that lower-end CPUs would see different results in these tests. As we’ve discussed before, DirectX 12 doesn’t really help you recover much in the way of GPU performance, though features like asynchronous compute can improve GPU perf in certain ways if supported in hardware. The major advantage of low-overhead APIs and the place where we always saw them do the most good was when paired with low-power or weaker CPUs, not GPUs. Here, they can make a significant difference, sometimes cutting CPU utilization by 10-30 percent and allowing for corresponding improvements in power consumption or giving developers more flexibility. We’ve also seen some specific cases where AMD’s DirectX 12 performance has given it better competitive standing against Nvidia, though again, the shifts here tend to be on the smaller side.
But at least in WoW, for now, the message seems clear. If you have a higher-end CPU and reasonably new GPU, DirectX 11 is the better API. We’ve got an eye on the situation and will re-test and/or revisit this question if Blizzard makes any formal announcements about improving the newer API’s performance relative to the older one.