I was so desperated about GPU acceleration and so4compound.dll plugin with Vegas Pro 15/16, after I saw this reply, it almost fixed all of my problems:
(Windows 10) Type GPU in "search" or search it in the "Settings", and it will shows the "Graphic Settings", browse the "Vegas150.exe" or "Vegas160.exe", click "Option" then select "High Performance", save and then exit.
After I changed this option I can use Cuda to having a very smooth preview, and no need to disable the so4compound.dll with my XAVCS footages, also no more problem to export the video with Magix AVC and NVENC template.
Thanks "Trensharo" and this is the BEST birthday gift to me! 😍