Can DirectX 12 finally handle World of Warcraft? This question was answered by a Reddit user, who two years ago was not thrilled with the performance of the last generation of DirectX libraries.

In recent months, World of Warcraft players' attention has been focused on the upcoming Shadowlands add-on and the recent update that prepared the game for the expansion's debut. However, some find time for other activities related to this popular MMO. This includes a Reddit user with the nickname samfishersam. Two years ago he tested WoW's performance using the newly introduced DirectX 12 library support. Now the internet user decided to repeat the test and see if this time the 12th generation DirectX would perform better than DirectX 11. He published the results via Imgur.

Assumptions of the test
Just like in 2018, samfishersam decided to run the test with the help of so-called Flight Paths. These connect different zones in WoW, and each journey using them follows almost exactly the same pattern. This, along with the ability to quickly repeat a flight, makes Flight Paths perfect for performance testing. The user took two routes from the Isle of Fangs in Zuldazar: to the Tortaka Refuge in Vol'dun and to the Forlorn Ruins in Nazmir. To be sure, after each test samfishersam completely closed the client and restarted World of Warcraft, and after turning on the game he waited two minutes for all elements to fully load. Additionally, samfishersam used ProcessLasso to automatically assign 8 CPU threads to the game instead of the default 4. All this to eliminate factors that could skew the test results.

Just like two years ago, DirectX 11 delivered a higher maximum frame rate than its little brother. That's the only thing the two tests have in common. For not only is the difference much smaller than in 2018, but in all other respects DirectX 12 performed better than eleven.

But far more importantly, DirectX 12 proved to be far more stable than DX11. Only the 1% percentile on the Zuldazar to Vol'dun run was marginally in favour of the older API - the flight to Nazmir saw a clear DX12 advantage. However, at the 0.01% percentile, the older API was twice as bad as its successor, which in practice means more lags, etc. DirectX 11 experienced drops to about 30 fps, while in the case of twelve the value of the 999th percentile was over 60 frames per second. It's slightly worse without the 8 threads being automatically allocated to the CPU, but even then DX12 was more stable than DX11.

In conclusion, if you play World of Warcraft, you finally have a reason to switch from DirectX 11. Or rather, "another reason" - recently revealed hardware requirements for upcoming games (from Ubisoft, for example) increasingly mention if not the necessity, then the recommendation to use DirectX 12.