Hello, I recently set up a new rig but I'm experiencing a strange problem with some renderers in MPC: Playback is smooth until I open up a menu or a balloon tooltip is shown (doesn't matter where on the screen), in that case CPU usage goes up to ~100% and framerate down to something like 0.5fps (you actually see the frame being drawn from top to bottom). After I close the menu smooth playback continues. Tested in vanilla MPC, guliverkli2 and MPC-HC. Affects VMR7 & VMR9 renderless, EVR and Haalis renderer. Overlay and windowed VMR are fine (but I cannot display subtitles while using them, among other things). Video resolution doesn't make a difference, both SD and HD res behave like this, as do different video formats and decoders. Videocard is a Radeon HD3850 with Catalyst 8.1 under WinXP. No such problems on my old system with a GF4Ti... Any help would be appreciated :cool:

This affects only Ati cards, AFAIK. I have the exact same problem that you describe with both a Radeon 9600 and a X800. In some thread somebody blamed it on Ati's windows GDI implementation. Nvidia seems to have got it right, though. This slowdown only seems to happen when using directx renderers that specifically takes use of gfx hardware.

Thanks. Your answer leads to some other questions: - Does this mean that VMR windowed does not use gfx hardware features? And is there a way of disabling it for renderless, too? - Does ATI acknowledge the existence of this problem, and if so, have they stated that it will be fixed? I don't have much hope though, considering that even the previous Radeon generations apparently have never seen a fix... :(

Windowed uses the graphics card's overlay, so it's still gfx, just not the directx path. I see this happen all the time. (It's actually any GDI windows painted on top that makes it stutter, menus are just the most common.) ATI kind of told me to bug off, but opening another ticket could never hurt.

No problems here (X800GTO+XPSP2+CAT8.1). The trick is to have AA disabled resp. set to application default.