Non-Existant. I haven't owned a desktop since early 2000's. I need to get everything from scratch!
FYI
Just before AHIII came online my video card started to fritz out on me. Reading a thread by Skuzzy concerning viable computer components that could be updated for optimum play, he stated that with the new game engine, the emphasis would be on the video memory, more than it was in AH2. The recommendation was getting a video card with 4G of memory. I bought the NVidia GTX980 with 4 GBs. I get 60+ fps all the time with all the eye candy, etc.