I upgraded my system from a Ryzen 1800x to a Ryzen 5600x, while at the same time upgrading from an NVidia 1060 (6GB) to an NVidia 3070.
Before the upgrade I benchmarked some encodes - the first was with DaVinci Resolve and the speedup was dramatic (it's easily 3-4 times faster), the second was a simple ffmpeg nvenc encode of h264 video and the performance of this encode is shockingly poor.
On the upgraded system nvidia-smi shows 100% encoding load during the ffmpeg encode, but CPU utilization is similar to single-thread levels. It's 30-50% slower than the old configuration! This is consistent regardless of which input file I use.
My command line is:
ffmpeg -i input.mov -c:a copy -c:v hevc_nvenc -b:v 1800k -maxrate:v 2400k -preset slow -sn output.mkv
Does anyone have any insights?