I know there's a similarly titled, unrelated thread.
This one is simply to thank Hendrik for implementing this fantastic feature. With this in place, I am seeing flawless 4K HDR 23.976 fps playback with integrated video from Intel i7 7700K, 8700 and AMD Ryzen 5 2400G.
These low end systems were struggling before, and sometimes, rendering times were 5-6x greater than they are now. For me, this is as big a leap forward for MC video as the original Red October introduction was for 1080p. When I go to AVSForum and see all the questions about getting 4K HDR to work well with MadVR, I sing Hendrik's praises again and again.
I use the high performance setting as a baseline, and then tweak a very few items that seem to improve performance for my systems. Finally, I think that a little more blurb on the Hardware acceleration checkbox in the Video options in MC is needed. It should say something to let the user know that it may actually degrade performance if checked. Further, it seems that the Optimize Hardware decoding and performance checkbox is unrelated to the Hardware Acceleration, as far as I can tell. Checking optimization when acceleration is off seems to have an effect. Or am I imagining it?