We usually suggest that you uninstall the stable and just run the dev builds so that there aren't any conflicts.
If you do want to run both, the create an empty .txt file named "portable.txt" and put it in the dev build main folder. This way it won't use the Global Directory.
If you're running the latest Nvidia drivers past 332.21, Nvidia introduced OpenGL 4.4, so Dolphin uses new instructions in 4.4 to achieve the same speeds as the Vertex Streaming Hack.
However, as of dev build 4.0-1192, OpenGL performance has taken a harder hit in performance than D3D because of an accuracy implementation.
If you do want to run both, the create an empty .txt file named "portable.txt" and put it in the dev build main folder. This way it won't use the Global Directory.
If you're running the latest Nvidia drivers past 332.21, Nvidia introduced OpenGL 4.4, so Dolphin uses new instructions in 4.4 to achieve the same speeds as the Vertex Streaming Hack.
However, as of dev build 4.0-1192, OpenGL performance has taken a harder hit in performance than D3D because of an accuracy implementation.