Should I buy this?

[MadHatter]

Hi everyone.  I am looking to setup my first jellyfin server and wondering whether this old Xeon based Mac from 2013 would be beefy enough to be capable of taking a single 4k video, playing it in 4k resolution on a TV, and simultaneously re-encode (downscaling the resolution) to operate on say a tablet and laptop at the same time as well?

The Mac is equipped with an E5 Xeon 2.7 Ghz 12 core processor, 32GB Ram, and a FirePro 6GB GPU.

From what I have gleaned so far it doesn't appear as though AMD GPU's fare very well so thought I would ask.

[Efficient_Good_5784]

If you want a cheap/low-power PC for running a Jellyfin server, I would look at getting a mini PC with at least an Intel N100 CPU so that you can take advantage of Quick Sync for HWA.

Without knowing much about the GPU, it looks like your transcodes will need to be done exclusively on the CPU on that system you're looking at using.
Should be fine if you can direct play all your media to avoid transcoding but not so much if you do need to transcode.

[Fate]

Well, yea the firepro is not that useful probably but the Cpu should be beefy enough for that.

The question is... that thing probably burns through a solid 200 Watts+ while doing that.. I don't know where you from but with that power draw it probably makes more sense to go for an n100 based mini pc.

[TheDreadPirate]

Well, yea the firepro is not that useful probably but the Cpu should be beefy enough for that.

The question is... that thing probably burns through a solid 200 Watts+ while doing that.. I don't know where you from but with that power draw it probably makes more sense to go for an n100 based mini pc.

Honestly not sure it can. Encoding is not as parallel as most people think.  At some point, single threaded performance will more important and an 11 year old CPU probably isn't up to the task, IMO.  Even with 12 cores.

And the GPU is pretty much useless for transcoding.

I'm hoping this is something OP already had and not something they bought.  Echoing Efficient with the N100 recommendation for a basic, but capable, Jellyfin server.

[Fate]

Well, yea the firepro is not that useful probably but the Cpu should be beefy enough for that.

The question is... that thing probably burns through a solid 200 Watts+ while doing that.. I don't know where you from but with that power draw it probably makes more sense to go for an n100 based mini pc.

Honestly not sure it can. Encoding is not as parallel as most people think.  At some point, single threaded performance will more important and an 11 year old CPU probably isn't up to the task, IMO.  Even with 12 cores.

And the GPU is pretty much useless for transcoding.

I'm hoping this is something OP already had and not something they bought.  Echoing Efficient with the N100 recommendation for a basic, but capable, Jellyfin server.

I think very highly of your knowledge but I think your wrong here.

Encoding is probably one of the best parallel CPU core scaling use cases there is. At least x264/x265.

The AV1 encoders are probably not that good (yet).

Don't forget that n100 is a 6W TDP part and an Intel Xeon E5 is a 130W TDP part.
According to passmark n100 has roughly the same single core performance:
https://www.cpubenchmark.net/compare/200...lver-J5005

We agreed on the GPU though

[TheDreadPirate]

Encoding is definitely parallel, but the rate of return as you add more threads is not linear above ~8 threads. At least with x264. I haven't tried with x265, but that is out of the question anyway with this old of a CPU.

[Fate]

Encoding is definitely parallel, but the rate of return as you add more threads is not linear above ~8 threads.  At least with x264.  I haven't tried with x265, but that is out of the question anyway with this old of a CPU.

x264 is probably the best developed encoder there is.

So many innovative concept and many rounds of speed optimizations went into it.

According to this diminishing returns sets in past 64 cores.
https://imgur.com/a/5Q9JpJp

And this is on ffmpeg 4.0 I can't imagine it getting worse in last years.
Unfortunately i couldn't find a similar well done Benchmark for x264 but since x265 borrowed a lot from x264 they should scale similar.
This was done on an Intel® Xeon® CPU E7-8890 v3 @ 2.50GHz
https://singhkays.com/blog/x265-128-core...-azure-vm/

I read somewhere x264 nearly scaled perfectly linear until you reach 40 vertical px per thread. 
So assuming a 1080p video scaling would diminish after 27 threads. (for 2160p or 4k it would be 54 threads)

Also OP asked about direct playing a 4k file and encoding a 1080p h264 at the same time.
Lets assume worst case we need:
2x 4k decode->encode 1080p+ overhead (audio+ whatever)
We don't need to scale to 12cores; we have 12 cores for 2 parallel encodes for x264 on the fastest preset. Easy.

And there is always the ultimate cheatcode: "mitigations=off" for another 25% more speed

[MadHatter]

Amazing input and very much appreciated. I've started exploring some of the N100 option(s) currently on the market and as a second option some older SFF systems into which I could plug in an intel arc GPU.