Plex Server Specification for 4K

General Discussions
1

I have an amazon fire TV box with the Plex app installed, and a Samsung 4K TV (also has a plex client, but I don’t use it). The amazon box can display Amazon Prime and Netflix 4K content on the TV with no issues, but I expect these are highly compressed. I also have a PC with a number of internal SATA drives that store my personal movie collection, running plex server. The Plex client on the Amazon box has no issues streaming 1080p HD quality content from the PC. Everything is connected with Cat 5e ethernet.

I recently downloaded some publicly available 4K content from 4kmedia.org - just a few minutes of different clips. These were HEVC encoded, and arrived in transport stream format (.ts files). I muxed them into a mkv container using mkvmerge, and added them to my library.

Upon playback, the PC CPU hits maximum, and I get a few seconds of content, before it stalls for 4-5 seconds, then gives me some more content. I get the message ’ the server is not powerful enough to convert this video for smooth playback’

Same message regardless of whether I set the client to ‘original quality’ ‘automatic’ or something lower.

So I guess it’s the PC, unable to transcode quickly enough. Given I built it in 2010, that’s maybe not a surprise - time for an upgrade…

It’s got an AMD Phenon II X6 1090T black, which is well past obsolete now (https://www.gamersnexus.net/guides/2898-amd-phenom-ii-cpu-revisit-in-2017-x6-1090t-1055t) for those who are interested, and 16 Gb RAM.

So, before I select a new mainboard, CPU, and RAM, would anyone be able to give some advice on systems they have that are working well? What should my main consideration be? I’m running linux mint, and don’t use this server for gaming.

Thanks,

Jeff.

2

As an experiment, I selected a 1 minute clip for playback, and paused it after a few seconds. The PC sat at max CPU for 5 minutes, and then CPU utilisation dropped to practically zero. When I pressed play on the plex client, the clip played perfectly, and the CPU on the server barely moved.

So I guess it took 5 minutes to transcode the 1 minute clip into something it could stream, and hold it in a buffer somewhere, such that when i played it back it transferred smoothly? Any insights on what is going on here?

Thanks!

3

You could try and increase the transcode folder to hold more, but basically the computer has reached it’s limits, when trying to do 4k.

I have found that in order to reduce issues, it’s always best to ensure playback can be done by direct playing and not streaming or transcoding. You may want to think about upgrading you player hardware instead of the server. The original files you downloaded may have direct played before the conversion.

4

A cheap & simple upgrade for your Plex client would be to install MrMC from the Amazon App Store. Under the covers it’s Kodi & does a much better job of playing media than the official Plex client for the Amazon Fire TV. It has a much nicer loom & feel too.

5

Thanks for the answers - the file I downloaded does play directly from a USB stick with no problems. Also, I used handbrake to re-encode the .ts file to another mkv, retaining the resolution. It came out at about 1/4 of the size, and the plex player was able to play it directly without transcoding, so little stress on the CPU. But it took 20 minutes to re-encode a 1 minute file.

Some further experimentation needed with a number of options needed I think, and I’ll look into MrMC as well!