i use all of those (and quite a few more) as docker containers, but have built a somewhat powerful machine with leftover components after upgrading my main computer: currently 32 GB of RAM and i5-7000 (or something similar, can't recall the exact model number).
since it's running OMV for the NAS side of things, it uses about 4-6 GB of RAM constantly and about 10GB for swap. it does need to transcode some files from time to time, but I'll just pause the stream for a minute or two and usually that's enough buffering leeway to watch the rest without having to pause.
in terms of CPU usage, even on the most computationally heavy days it rarely uses more than 40% of the CPU
i use all of those (and quite a few more) as docker containers, but have built a somewhat powerful machine with leftover components after upgrading my main computer: currently 32 GB of RAM and i5-7000 (or something similar, can't recall the exact model number).
since it's running OMV for the NAS side of things, it uses about 4-6 GB of RAM constantly and about 10GB for swap. it does need to transcode some files from time to time, but I'll just pause the stream for a minute or two and usually that's enough buffering leeway to watch the rest without having to pause.
in terms of CPU usage, even on the most computationally heavy days it rarely uses more than 40% of the CPU
hope this info helps somehow