Try dropping the ram to even numbers. You should be able to get 4 or 6 cpu's for AE and 4 or 2 for other apps. Todd has a link to an article on setting up MP for your machine, but I have to say again that if you are using temporal effects or codecs or 3rd party plug-ins that are not MP aware turning MP on will slow down your render and could cause lots of other problems. I keep it off 95% of the time, use AM to do 99% of my rendering, and seldom if ever stop working and let AE grind out a render. Every time I stop creating or editing a project in AE to push out a render I'm loosing productivity. Finish a shot, load it into AME to render, start the render, then move back to AE to work on another shot, or to PPro to edit, or somewhere else to be productive. Hopefully you can get to the point where you will not need to see a full rez, full length ram preview of your project to know what it will look like when rendered.
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