poor dvd playback on Pentium M 750

[Jack Howarth]

      Is there a particular reason why DVD playback is so choppy on
Pentium M laptops (a 1.86 GHz model 750 chip in this case)? I tried
xine, vlc and mplayer on Fedora Core 4 installed on a Dell Latitude
D810 and in all cases the playback stutters. This machine has the
ATI X600 graphics with the newest v8.16.20 driver livna packaged
driver installed. I am quite surprised by this since even a 450 Mhz
G4 with ppclinux could handle DVD playback smoothly leveraging
the Altivec support. I assumed that the mmx support on the Pentium M
would have provided as least as much performance but that doesn't 
appear to be the case.
             Jack