XV performance problem on Ubuntu 9.04 Intel 915/945

[Ken Mandelberg]

I've upgraded a few laptops that from Ubuntu 8,10 to 9.04. These have
either Intel 915 or 945 graphics chips. .

The xvideo performance has gotten much worse after the upgrade. The
video is jumpy at 720p or 1080i where it wasn't before.

I'm guessing that this is because of the Intel Xorg driver which moved
from 2.4.1 to 2.6.3 in the upgrade. Both Intel chips use the overlay xv
driver, and I made sure that XvPreferOverlay is on in xorg.conf. xvinfo
confirms that the overlay (not textured) is the default xv port as on 8.10.

In either case xvmc is disabled, and I don't really see any significant 
differences in the Xorg logs. I can post them if anyone thinks that 
would be useful.

Is there something else I'm missing? The performance is just too bad to 
be used on on 9.04 with the usual set of media players at the higher rez's.