А это с форума Адоба:
I recently bought a Mac Pro in Aug 2012 with 12 cores and 16GB RAM and took the advice of my local Apple Solutions guy that a ATI Radeon HD 5870 would be worth the extra money to speed up my work flow in CS6.
A month into using the machine I discover to my surprise that After Effects CS6 will not use the GPU on a ATI card, only an NVidia card! Putting to one side the appalling lack of knowledge of my Apple Solutions guy is there any news on if and when ATI GPU's will be used by a CS6 update or would I be better off taking the financial hit and buying a NVidia card to replace my ATI one as I just rendered a 6 second 3D extruded text animation 320x240 that took 6 minutes to render which only takes 7 seconds when using classic 3d renderer!
I think in hindsight spending more money on your GPU is better than having lots of CPUs!
http://forums.adobe.com/message/4672468