How much CPU usage is reasonable?

[brainyyak]

Hardware:

Mobo: Supermicro X9SCM

CPU: Xeon E3-1225

RAM: 8GB of something random and compatible off ebay

Unraid version 6.8.3

 

 

I recently completed my Unraid NAS build, which I will be using mostly for media storage and plex, but I also am running a factorio server occasionally as well. While plex is being used, I notice on my dashboard that 1 of my 4 cores will be pinned to 100% usage. After about a minute or so, it switches to a different core being maxed. Meanwhile, the other cores are chilling around 1-5% usage. My CPU temp is staying reasonable and I'm not having any issues with playback, but my intuitive sense is that using any part of my system at the absolute limit is not good. Is this normal and reasonable, or do I need to get hardware transcoding running on a GPU? I'd rather not pay for plex pass if I can avoid it. At most, I'd be expecting my server to handle 1-2 streams of video ranging from 480p-1080p.