Ram Preview frame rate depends on your settings, your comp, your free memory, your drive speed and a bunch of other things. CC 2015 isn't as good at playing back in real time as previous versions. Without knowing any details the best I can suggest is to make sure that your composition is not bigger than 1080 X 1920, that the Zoom Factor (Magnification Ratio) for the comp panel is 50% or less and that the Comp Panel resolution is set to Auto. If you can't get the comp to playback in real time try changing the zoom factor to 25% which will automatically change the Comp Preview resolution to 1/4. If the resolution is not wrapped in parentheses then you don't have it set to auto:
If none of that works, make sure that AE and your OS are up to date, that you have no third party programs installed that may cause problems (that list is fairly long), and that you have sufficient room and speed on your cache drives.
Dear Rick, thanks for fast answer. Everything, what you wrote up i did. Programs cant influence on AE, because i'm specially install again windows, and after load drivers install AE, without changes. There is another option in what could be the problem?
There is an update coming out for CC 2015 "at the end of the month" according to Adobe folks. So, until that comes out, try using CC 2014 and see if it behaves better.
SHAME ON YOU.
i have a very fast system. i'm tech savvy, and nothing has changed on my end. you BROKE the ability to preview (ram preview) in realtime.
this is NOT acceptable, and it's a HUGE problem for production output and efficiency.
i'm simply bewildered at this. this is not an improvement. everyone is talking about settings, hardware, etc as part of the issue, but the truth is you simply broke the software, and it doesn't work now.
SHAME ON YOU.
GET IT TOGETHER.
Adobe, you should offer your AE users a discount until you can get this fixed.