How to do hardware accelerated encoding on GeForce 820M ,it is an older Fermi GPU?

My system has GeforceGT 820M GPU and driver version is 376.54 . I know it is an older Fermi GPU architecture and does not support NVENC so i want to know how we can do hardware accelerated encoding on such type of old GPUs.

I am unable to find NVCUVENC sample code if any one has knowledge about it please share the link.