the point is this…
hevc is extremely processor intensive, so much so that using the GPU is generally a better option for on the fly transcoding.
as already noted, a single 4k hevc transcode to 1080 x264 takes about 17000 passmarks PER stream/transcode.
this is a lot to ask for the CPU.
whereas with a suitable GPU (and plex pass to enable it), the GPU can offload the video transcoding, so less cpu power is needed.
most (but certainly not all) modern intel cpus already include a gpu built in that handle several HEVC transcodes without the need to purchase a separate GPU.
alternatively, for an older cpu, adding a newer nvidia card with GPU transcoding capabilities, can help avoid the need for a new cpu/motherboard/etc.
if you do not want to pay for plex pass, then your only option is the most powerful cpu you can afford.
either way, you pay the piper, because transcoding hevc is NOT easy.
you may find some further learning @ Plex, 4k, transcoding, and you
