Dota 2 is now running on Valve's shiny new Source 2 engine and although the response has been mixed, it should result in a faster, more feature-packed base for the developer to build on. If you're willing to brave possible instability, you can get a taste of future improvements right now.
As Reddit user "Anaron" warns, the tweak is easy to activate, but not necessarily that stable and your experience will differ based on the hardware your PC is running.
The guts of the tweak is the adding of
-DX11 to the game's start-up arguments. You'll need to know the location of the Dota 2's 64-bit executable, which will almost certainly be in your Steam folder under
SteamApps\common\dota 2 beta\game\bin\win64\dota2.exe. You can then use it to create a shortcut and add the argument.
If you just want Direct3D 11 with the 32-bit executable, you can just plop in the command via Dota 2's Steam entry in the usual way.
From reports on Reddit, you could see massive performance gains... or it might crash relentlessly at the main menu. If you give it a go, be sure to share you experiences.