But if you say you didnt enable post processing how can you be sure DXVA will not be affected? Again, to my best knowledge you have to set ffdshow to pick up any uncompressed video (=any decoded stream), so it will force itself in every stream you'll play?
I think when hoborg says post processing, he is not talking about adding the ffdshow filter to post processing, he means when ffdshow codec is in use it will be upscaling etc..