I've got a recent Mac Pro with 6GB of memory running After Effects CS3, but my Ram previews are quite brief.
In one sequence, I managed to get about ten seconds of Ram preview. But when I duplicated that sequence and made a minor tweak, then tried to Ram Preview it, I only got half a second's worth of preview.
It seems odd that it's not using up the memory that was used in the earlier sequence and allocating it to the newer sequence, (the green bar still shows ten seconds worth of preview time on the older sequence).
What am I doing wrong?