I am going to upgrade the processor in my server, I recently installed plex media server on it to get rid of having two computers. Anyone know how many 1080p transcoding streams this processor can handle?

look up the futuremark PASSmark of the processor and assume ~1500-1700 2000 points per 1080p stream. That will be your answer.

 

Sauce if you want it: https://support.plex.tv/hc/en-us/articles/201774043-What-kind-of-CPU-do-I-need-for-my-Server-computer-

ahh that helps thank you!

I've seen guys claiming 1500 passmark per 1080p stream would suffice, but of course its always better to be on the safe side than regretting later.

 

https://forums.plex.tv/index.php/topic/116485-qnap-ts-x51-series/?p=707043

yeah as always it will depend on what you are coming from. As you can see I originally put 15-1700 because not only does that jive with info from elsewhere, but also my experience from loading up my server with full rate BD rips (i.e. 50mbps streams) transcoding to <5mbps

The transcoding isn't purely dependent on the CPU, but also on the acceleration capabilities of the video adapter.  Assuming you're using the on-chip video (HD4600), this has excellent capabilities, so I'd expect 1500-1600 passmarks/stream is pretty accurate.    With that CPU's PassMark score (7041) you should easily be able to handle 4 simultaneous streams.

 

hmmm i was not aware that plex media server used the GPU in linux (or even windows). Given my ATI Rage video card I can say for sure my GPU is not contributing at all. Based on very shallow searches of plex forums, the cpu does all the work.

 

EDIT: https://forums.plex.tv/index.php/topic/117318-cuda-transcoding-support/?hl=cuda

There are conflicting threads r.e. whether or not Plex using GPU assist when transcoding.  This post from a year-ago indicates it DOES use GPU acceleration for at least part of the process:  https://forums.plex.tv/index.php/topic/92874-gpu-offloading-timed-library-refresh/

 

... hopefully it's even better today; but as I noted it's difficult to confirm that.

 

In any event, an i5-4590s is an excellent CPU and I'm sure it can support at least 3 simultaneous streams even without GPU hardware assist; and should easily support 4, or possibly even 5, if it in fact uses the GPU to assist in the process.

 

Regardless of GPU, I agree 3-5 is reasonable. I ran 4 streams with my FS8320 (8000 passmark) from the aforementioned BD rips as a test. I could see the cpus (all were working very hard, but they weren't maxed once the streams were buffered sufficiently.

Well from all this, I will probably go with it. I tried doing several 1080p streams from my gaming computer (i5-4670k) just to get an idea of how many I might be able to do, and I ran out of devices to transcode to.    I think I used 7 devices? all wireless. So it looks like everything will be fine with my setup. Thanks guys

Clearly you've already proven that there's more "horsepower" than you need in the CPU.  Your 4670k is only 9% more powerful than the 4590s (PassMark 7676 vs 7041), so at most there would be a single stream difference in the capabilities.

 

You know, I wonder if the last 6 months to a year of optimizations into the new plex transcoder (they use a customized version of ffmpeg) have lowered the "required" passmark score per stream. [shrug] Good news in any case.

Given that a year ago they were using some of the GPU acceleration capabilities, I suspect it's likely that they're taking even more advantage of this ... which will clearly lower the demands on the CPU [thus lowing the "PassMarks/stream" requirements on the CPU].

 

an easy way to find out, get a few streams going and monitor the GPU temps.