Slower than expected using YUV overlays under XFree86 4.0


I just got XFree86 4.0 up and running. And I thought i would try out the new
Xv support in SDL so i used mpeg2dec to try it. Only problem is that it is
not any faster than it was under XF86 3.3.6 without the Xv support. I have
recompiled the SDL libraries and also mpeg2dec. And yes, I do have a matrox
G200 so the drivers support Xv and SDL detects the Xv extension properlly
when configuring. If I run mpeg2dec without SDL, just using X11 directly
(using Xv) it became alot (25-30%) faster.

Is there something special i have to do to enable hw Xv-images in SDL?

Also. How do i turn off the use of DGA without recompiling the entire lib?

Thanks in advance
Mattias Blomqvist