Failed to open NVENC codec: Function not implemented

[BadBaguette]

Trying to run OBS on Ubuntu 21.04 with NVENC encoding, and get this error when I try to record:

"Failed to open NVENC codec: Function not implemented
Please check your video drivers are up to date."

I am using the Ubuntu-recommended NVIDIA driver (version 390). My GPU is a GeForce GT 730. I noticed NVIDIA lists a more recent driver for my GPU on their site, version 460. However I am unable to install this driver (installer says it's not supported for my GPU, contrary to the information on the website).
Is my current driver the issue? If I'm supposed to be using version 460, and if so, how can I install it?

Thanks a bunch in advance

 

[BadBaguette]

For clarification, I would like to use NVENC (if possible), not circumvent the solution by switching to software encoding.

 

[Tuna]

Since that particular GPU is not listed on NVIDIA's supported cards for NVENC:

Video Encode and Decode GPU Support Matrix

Find the related video encoding and decoding support for all NVIDIA GPU products.

developer.nvidia.com

..it is most likely simply missing NVENC support.