For MPEG-2 playback tests, we ran The Matrix DVD, a personal favourite of mine on each system with Hardware Acceleration enabled to check for smoothness of playback as well as CPU usage during the test. The result was with 30 minutes of playback and the CPU utilization is the average.
Having a dual core Atom didn't really reduce much CPU time when running the movie. However, the thing we noticed was when we swapped out tasks such as running a flash program on Facebook in the background, we didn't stall out like the Atom 230 did. CPU usage went up to around 46% where the Atom 230 hit 95% and would sometimes stall out. The Nano was about the same as the Atom 330 in these tests when it came to multi-tasking.
Playback for MPEG-4 was again done with the Matrix, only encoded down to MPEG-4 DIVX 6.8 codec. 30 minutes was the time run. Smoothness of playback, audio sync and CPU usage are the keys here once again.
Now into MPEG-4 playback and this is where the Atom 330 manages to really shine. Compared to the 230 CPU, usage was much lower, but still not able to keep up with Nano. However, playback was smooth and while multi tasking we managed to keep the playback smooth and running where Atom 230 stalled out quite a bit.
Using the Matrix again encoded in 720p we did our playback tests again, a 30 minute run was done with Smoothness of video, audio/video sync and CPU usage the big things as well as multi-tasking.
Atom 230 failed this test terribly with Atom 330 not far behind. CPU usage was way too high. Atom 230 could not play back the movie at all; it would simply jump all over the place. Atom 330 managed to run a bit smoother, but not really at all watchable. Only VIA Nano was able to play back the movie successfully. However, multi-taking was out of the question.