i thought i had a pretty good computer, i thought it would be really fast, but when i got after effects its RAM preciew isnt working that good.
For instance i bought Evolution from Video Copilot and when i get multiple layers of effects from in on my comp and RAM preview, its starts to render the preview, but it gets to a point where the green bar above the clip where it started Rendering starts moving, like it goes away, and is forever stuck in rendering the whole preview.
Why is this happening?
Second, how can i make After Effects Render better?
Not entirely clear about what you're describing with the green bar. Are you saying that as you RAM preview, after a while it will stop adding to the RAM preview (shown by the green bar) and taking away the old frames that were RAM'ed? This happens when the computer can't keep everything in the RAM preview, so you have to preview in sections. It happens.
8 GB of RAM is great, but you only have a single processor, it seems (or is that a quad core?). AE can only use a certain amount of RAM per core (i think it might be 3GB?) so the extra isn't being used. If it is in face a multiprocessor, you can go into the AE preferences and enable multiprocessing. I haven't done this so i'm not sure how it works, but my understanding is that it will speed up your previews.