I’ve used parts from my old PC for my Homeserver. Among other things, it runs Jellyfin. Most of my library can be directly played by most clients, so I need almost no transcoding. Just serving the media uses tiny amounts of ram and compute, and the only bottleneck I could see is a residential Internet connection (I’ve got symmetrical gigabit, but there’s lots of residential gigabit that limits uploads to like 50mpbs).