Question : Multlicore+Cuda. vs Latest Cuda.?

Hello, developers!
I am beginner of the cuda and one of members in the project.
But i have a strange question appeared when i heard about stories from a former worker.
He made a 3d-camera with multicore + cuda for accelerating to camera operation from 5 years ago.

I am not clearly understanding about cuda and gpu but, according to my knowledge of GPU device, Gpu device is made of multiple cores for parallel operations from host. So I thought about this statement as no difference between gpu devices and multicore process.

If you have any ideas to relate with my topic,
PLEASE tell me or teach me what is wrong!

Thank you.