^~20-25% CPU usage is normal for decoding 1080p H.264
CoreAVC supports DXVA, and so does KMPlayer (I guess). Download and install CoreAVC v1.9.5, it supports DXVA
DXVA does not work with DirectVobSub(VSfilter) or for that matter any other filter acting b/w the video decoder and video renderer.
If you want subtitles, you must use MPC. Use EVR Custom Presenter as video renderer, enable auto subtitle load, and block DirectVobSub from external filters.
Will be posting a full-fledged guide on x64+x86 filters, splitters, players and more within a day or so
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