nvEncodeAPI.h not found.

While tryiny to install the latest ffmpeg that support “nvenc” , i got the following message after runnnig “configure” : ERROR: nvEncodeAPI.h not found.
I have a geforce 210 with 1 GB DDR3 with 16 Cuda cores . my question is simple : When i have so much cores that no serve to use the nvencoding capabilities, why are we using a computing in the 21 Century ?
Thank you

PS : i will not buy an anotha nvidia Card untill i get good and humble support for my Geforce 210 .