RT preview in AE via Cinewave

Yo...

Is it possible to RAM preview in realtime speed in AE via Cinewave using the Video Preview option ?

I did some simple animation and used the ram preview but it was playing around 12/15fps rather than 25fps(PAL), even when previewing in half res.

I've got 1.5GB ram on my system...anything I should set or it's just not possible to achieve RT playback in AE ?

I can get RT preview in Commotion though...using the Preview DV option...that's what I am looking for in AE.

Thanks,

-chrispy

Also, YUV16 preview seems not supported at all so in order to see what 16 RGB in 10 bit YUV video looks like you will need to render as well. This is kind of a drag.