Looking at the Ryzen 9 3950X 16 core for plex..Will that CPU do well with transcoding?

jordan12

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So I currently have a 4790K and transcoding sucks. First time with an AMD, and someone said that they have come a long way.

So would that CPU do well for plex?
 
Why don't you enable hardware encoding and use the QuickSync off of your existing CPU's IGP? Probably cheaper that way. Or get a cheapish video card with NVENC to do the transcoding.

But yes, for pure CPU transcoding the 3950x will run circles around a 4790k. How many concurrent streams do you have at a time?
 
Why don't you enable hardware encoding and use the QuickSync off of your existing CPU's IGP? Probably cheaper that way. Or get a cheapish video card with NVENC to do the transcoding.

But yes, for pure CPU transcoding the 3950x will run circles around a 4790k. How many concurrent streams do you have at a time?
I would like to have 3 streams. I hit more than 1 and the second one starts pausing and unpausing, etc
 
Did you ever try hardware transcoding via your IGP or a video card? I mean if a Synology box with a low powered celeron will transcode multiple 4k streams using QuickSync, I see no reason not to at least try it.
 
Did you ever try hardware transcoding via your IGP or a video card? I mean if a Synology box with a low powered celeron will transcode multiple 4k streams using QuickSync, I see no reason not to at least try it.
I turned that on.
 
My 12-core 3900X handles real time plex transcoding of 4k h.265 great. I wouldn't have minded the extra few cores though, as I don't think I can do two simultaneous 4k stream transcodes at the moment.

For anything less than 4k h.265, it can probably handle as many streams as I can possibly throw at it.
 
The real answer is grab a more modern Intel CPU with updated QuickSync. Check the support matrix here to select a part that makes the most sense:

https://en.wikipedia.org/wiki/Intel_Quick_Sync_Video

The hardware acceleration will absolutely out perform just chucking more CPU at the problem.

You can also look up adding a low cost Quadro to use NVENC if you want to avoid replacing the entire system. There's a bunch of threads on the Plex forums about this stuff.

I'm running an old E3 v2 Xeon but I direct stream all of my 4k content and don't share that library outside of my LAN, so take my advice with a grain of salt from someone who has only read up on this.
 
Yes, I agree. I use an i5-6500 in a cheap HP mini PC and it handles 4 hardware 1080p transcodes no problem. You want Skylake or later, ideally Kaby Lake for full HEVC support.

That said a 3950X will certainly do the trick too in software, and will handle more simultaneous transcodes. But you'll use a lot more power and it's much more expensive to boot.
 
I'm not doing plex transcoding like you are. I'm transcoding from Blu-ray to MP4 using Handbrake (2-pass). But I've kept a spreadsheet of data on the transcoding (using Handbrake, 2-pass, 3000 kbit/s) of the same file on various CPUs that have passed through my hands over the last few years (would love to upgrade the 3950X to a 5950X, but that doesn't look like it will happen anytime soon due to availability). This might at least give you an idea of the relative performance of the i7-4790K (~ like my i7-4770K) and the Ryzen 9 3950X. I had an i7-4790K for a short while, but unfortunately, I didn't bench it with the same version of Handbrake (the 4790K was about 13% faster than my 4770K in an older version of Handbrake).

Handbrake transcode.png
 
So I currently have a 4790K and transcoding sucks. First time with an AMD, and someone said that they have come a long way.

So would that CPU do well for plex?
Most of the current CPUs would do better than your current i7-4790K. The i7-4790K had been lingering in "legacy" support status for a few years now: All of the newer iGPU drivers since about 2017 for that CPU had been merely security fixes to a driver that dated all the way back to 2015. And newer plex programs are now requiring a newer iGPU (and thus a newer version of QuickSync) just to even enable hardware encoding at all. Such depreciated support from Intel itself for a CPU that I had used in my main PC for over five years is the biggest reason why I upgraded from that CPU to an AMD Ryzen 7 3800X back in December of 2019.

And a discrete GPU with NVENC cannot come anywhere close to fully compensating for the deficiencies of that i7-4790K: Even a TOTL GPU with NVENC support will still leave the i7-4790K slower than even a cheap newer-gen CPU with a middling-performance Nvidia GPU.

Now, if you're going to encode into other codecs besides H.264 and HEVC, then the Ryzen 9 3950X is an excellent choice.
 
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