I downloaded some 720p and 1080p trailers to test under Ubuntu in my new laptop, but Xv would crash and no video player was able to playback them. For large video resolutions you need this on your xorg.conf if you are using the i810 driver, or you’re toasted. Small-sized videos work fine out of the box.
Option VideoRam XXXXX (write how much VRAM you got)
Option CacheLines 1024 (use more if the video has more vertical lines)
So, after my changes I restarted X and what do you know? 1080p video is smooth as butter on this 1.66 Ghz CoreDuo laptop with 1 MB cache! If I had opted for the 2MB cache/2.0 Ghz Core2Duo instead the speed would have been considerably better even! It’s cool, because my other laptop, a 2.8 Ghz P4 and even my desktop a hyperthreaded 3.0 Ghz P4 can’t render 1080p without dropping frames! It’s amazing what Intel and AMD have accompliced the last few years without having to continue that pointless megahertz race!