More RAM won't fix 4K transcoding buffering.

No. That buffering is almost certainly a CPU or GPU problem, not a RAM problem.

Plex transcoding, especially 4K, is a compute-heavy job. The video stream needs to be decoded and re-encoded in real time. That work happens on the processor (or a dedicated GPU if you have hardware acceleration enabled). More RAM won’t make the encoder go faster — it’ll just sit there being empty while your CPU chokes.

16GB is actually plenty for a home server running Plex and a handful of Docker containers. Transcoding uses system memory for buffers, but even a single 4K transcode only needs a few hundred MB. The rest of your RAM handles the Docker overhead and maybe some caching. Unless you’re running 20 containers that each eat a gig, you’re fine.

If you’re seeing buffering during 4K transcodes, look at your CPU’s PassMark score (Plex recommends 2000+ per 1080p transcode; 4K needs at least 12000 for software encoding) or enable hardware transcoding if your CPU/GPU supports it. Storage speed could also be a factor if your media is on an old spinning drive.

Don’t throw RAM at a silicon problem.