I have a new imac 27" with GeForce 780m graphics card, it's apparently one of the cards that adobe accepts for GPU Acceleration but the option in After effects doesn't allow it? Can it be done or am I getting it all wrong, any help would be great.
You have to install the Cuda driver and then, you may have to check the option to enable the driver in preferences.
What version of AE are you using (down to the last decimal point)?
Read this for info on what AE does and doesn't use the GPU for: GPU in After Effects
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