Heroes of Might and Magic V: Tribes of the East (Steam license) is lagging.

By the way, you can also put all the DirectX .dll files in the game's bin folder – start with d3d9.dll (attached – you need to unpack d3d9.zip) and so on, so that the .exe file unambiguously uses the libraries from DirectX 9.0c!

And also, does it only lag in the main menu or in the game as well?! If the answer is yes, then there is a mini-mod attached that disables the main menu... unpack the ascetique.zip file and place the ascetique.h5u file in the game's UserMODs folder!