|Also, if you're playing DRMed WMV, you need to set the renderer under Options / Settings / Windows Media...|
|As far as dropped frames... I'm on a much weaker machine (p4 2.53) on a weaker AGP card (GF4 TI4200) and I'm not getting dropped frames. Don't really see a reason why you would. There are a few parameters that are tweakable, but I think I'm setting them to the best quality right now.|
|I have nothing to compare playback against as the NVIDIA player is buggy for me and mediator is even worse, only playing DVDs.|
|Also, make sure you're not using reclock, it may cause issues with renderless mode. And you should be aware that ZP isn't controlling the panning or anything else, the renderless structure doesn't quite work like that. ZP just tells it how many VSync to wait before displaying the image, the resolution of the textures (same resolution as video), the resolution of the back buffer (same resolution as active monitor). Not too much is at play here.|
So how many VSync are you waiting for? You have fewer of these to play with as the resolution goes up. You should also have control of the number of back buffers and VMR buffers being allocated.
I hope this helps to point you to the issue.