4K Plex Server CPU Recommendation

[Durvelle27]

What’s up guys. Been out of the scene for a little but I’m trying to put together a Rig/HTPC for 4K playback as a Plex Server strictly as cheap as possible. I tried using a Pentium based build but the 4K playback constantly lags and buffers with the CPU pegged between 90-100% load. Do you guys have any recommendations

I already have a case, HDD, PSU, and OS

 

[dorsetknob]

I tried using a Pentium based build but the 4K playback constantly lags and buffers with the CPU pegged between 90-100% load.

Can you supply us the Info on the Board and CPU you have tried ?

 

[Kursah]

I'd probably go no less than a higher-end i3 or more likely, i5's or better for 4K streams. Plex also supports GPU transcoding so that might be an option too. But ya it does seem a Pentium isn't going to handle it, though maybe if you have a spare GPU you could use, that might help mitigate the need for a different CPU, MB, etc.

Here's some more info: https://support.plex.tv/articles/115002178853-using-hardware-accelerated-streaming/

Plex server system requirements: https://support.plex.tv/articles/200375666-plex-media-server-requirements/

Plex does recommend an i7 for 4K transcoding: https://support.plex.tv/articles/201774043-what-kind-of-cpu-do-i-need-for-my-server/

I don't stream 4K, but my virtual instance of Plex with 4 threads from my 4790K handles my 1080 streams with ease.

 

[hat]

You'll need a beefier CPU to transcode 4k for sure. Plex can direct steam though if the target device natively supports your content, which poses no impact on the server besides just sending data.

 

[Durvelle27]

Can you supply us the Info on the Board and CPU you have tried ?

I can’t remember the model right now but I know it’s a dual core @2.8GHz and 4GB of DDR3

I'd probably go no less than a higher-end i3 or more likely, i5's or better for 4K streams. Plex also supports GPU transcoding so that might be an option too. But ya it does seem a Pentium isn't going to handle it, though maybe if you have a spare GPU you could use, that might help mitigate the need for a different CPU, MB, etc.

Here's some more info: https://support.plex.tv/articles/115002178853-using-hardware-accelerated-streaming/

Plex server system requirements: https://support.plex.tv/articles/200375666-plex-media-server-requirements/

Plex does recommend an i7 for 4K transcoding: https://support.plex.tv/articles/201774043-what-kind-of-cpu-do-i-need-for-my-server/

I don't stream 4K, but my virtual instance of Plex with 4 threads from my 4790K handles my 1080 streams with ease.

1080 playback works perfectly fine just 4K is unpleasant

You'll need a beefier CPU to transcode 4k for sure. Plex can direct steam though if the target device natively supports your content, which poses no impact on the server besides just sending data.

Devices should

1x Xbox One X
1x Xbox One S
2x Smart TVs with Plex Built in

 

[Kursah]

I can’t remember the model right now but I know it’s a dual core @2.8GHz and 4GB of DDR3


1080 playback works perfectly fine just 4K is unpleasant


Devices should

1x Xbox One X
1x Xbox One S
2x Smart TVs with Plex Built in

Out of those, how many are displaying in 4K?

 

[Durvelle27]

Out of those, how many are displaying in 4K?

All of them when viewed are viewed in 4K

 

[neatfeatguy]

No issues with a couple of devices running 1080p on my i5-4460 Plex server. Also a few outside devices stream 720p (limited to 720p due to my upload speed) - even with all 4-5 pulling videos at once we don't experience any hiccups. Usually it's no more than 2 at a time, but every now and then everyone's looking to watch something off the server.

Clearly they recommend an i7, but perhaps if you can find a decent i5 (cpu/mb combo) at a good price it might be worth trying out.

 

[FordGT90Concept]

I assume Plex uses FFMPEG which means the more cores the merrier. I'd use a Ryzen 6-8 core.

 

[Kursah]

All of them when viewed are viewed in 4K

Depending on the device that should minimize the need for transcoding if the source file is something the remote device can play natively. If that isn't the case then transcoding will still have to happen, and on top of that much more network bandwidth must be used to stream the file over to the device.

How is your home network setup?
Are all of these devices wired on Ethernet, is it 100Mbps? 1000Mbps/Gigabit?
Are anyconnected via WiFi?
If connected to WiFi, what is the connection rated at? N150/300? AC867+?

Check out the links I shared in my previous post as well, should provide some good information for possibly utilizing GPU transcoding and/or what you may consider moving forward. I also agree to consider a Ryzen build...like the one in your system specs or more. You could even run a test Plex server from your system, stream a 4K movie and see how it performs as a reference.

 

[FordGT90Concept]

A single 4K stream can use upwards of 60 Mbps.

 

[CrAsHnBuRnXp]

What are you using to RIP the 4K Blurays? I am also looking to add 4K content to my server.

A single 4K stream can use upwards of 60 Mbps.

There is a new video standard (cant recall the name of it atm) but it will allow the compression of say 10GB 4K video files down to 3GB or less.

Edit: Here it is

 

[FordGT90Concept]

Video: MPEG4 Video (H264) 3840x2160 25fps 31397kbps [V: Alias Data Handler [eng] (h264 main L5.1, yuv420p, 3840x2160, 31397 kb/s)]
Audio: AAC 48000Hz stereo 317kbps [A: Alias Data Handler [eng] (aac lc, 48000 Hz, stereo, 317 kb/s)]

AV1 is supposedly 30% more compact which would translate to a still-heavy 22200 kbps.

Since OP is in USA, it's more likely to be 30 fps than 25 fps (the source I used above was produced in Poland) so expect 20% more bandwidth requirement than given.


I'd be most concerned about those two TVs. If they don't support whatever encoding the videos are in, Plex is going to make the server transcode.

 

[cdawall]

You can use an nvidia gpu for a maximum of two streams, but it'll do 4k fine.

Even my 16 core broadwell e xeon cannot do 4k transcoding

 

[Durvelle27]

Depending on the device that should minimize the need for transcoding if the source file is something the remote device can play natively. If that isn't the case then transcoding will still have to happen, and on top of that much more network bandwidth must be used to stream the file over to the device.

How is your home network setup?
Are all of these devices wired on Ethernet, is it 100Mbps? 1000Mbps/Gigabit?
Are anyconnected via WiFi?
If connected to WiFi, what is the connection rated at? N150/300? AC867+?

Check out the links I shared in my previous post as well, should provide some good information for possibly utilizing GPU transcoding and/or what you may consider moving forward. I also agree to consider a Ryzen build...like the one in your system specs or more. You could even run a test Plex server from your system, stream a 4K movie and see how it performs as a reference.

So far I’ve tried 4 different Movies on all the devices and at some point it buffers during playback so I would assume they are all transcoding for some odd reason.

My LG 4K TV is Wired
Xbox One X is Wired
All the rest is wireless utilizing Wifi 5GHz AC
WiFi Connection Rated for 1300Mbps on 5GHz
ISP Speeds is for 300/50

I read the link a little and I see the GPU must support H.265 decoding which I would assume only newer gens do

Actually I no longer have the rig in my specs tragically, I just never got around to remove it

What are you using to RIP the 4K Blurays? I am also looking to add 4K content to my server.


There is a new video standard (cant recall the name of it atm) but it will allow the compression of say 10GB 4K video files down to 3GB or less.

Edit: Here it is

ATM I’m not ripping any Blu-rays. My collection consists of disc and digital copies through Ultraviolet and Amazon

 

[cdawall]

I read the link a little and I see the GPU must support H.265 decoding which I would assume only newer gens do

You can slap a GT 1030 in it to do a single stream of 4K from what I understand, but most recommend a 1060 3GB.

 

[Jetster]

Newer Intel 7th gen CPUs have way better 4K playback. Better than most older GPUs

Also I don't care for plex on local playback. It tends to decrease sound quality.

 

[neatfeatguy]

What are you using to RIP the 4K Blurays? I am also looking to add 4K content to my server.


There is a new video standard (cant recall the name of it atm) but it will allow the compression of say 10GB 4K video files down to 3GB or less.

Edit: Here it is

I'd hate to see what a 4k video size is not compressed. Since I'm still in the process of copying my DVDs, just the other day I pulled a copy of Finding Dory from Blu-Ray and it was 20+GB in mkv format. Changing it over to mp4 and it went down to about 6GB. Using AnyDVD+Handbrake and Blu-Ray would be 3.5-5GB.

So far I’ve tried 4 different Movies on all the devices and at some point it buffers during playback so I would assume they are all transcoding for some odd reason.

My LG 4K TV is Wired
Xbox One X is Wired
All the rest is wireless utilizing Wifi 5GHz AC
WiFi Connection Rated for 1300Mbps on 5GHz
ISP Speeds is for 300/50

I read the link a little and I see the GPU must support H.265 decoding which I would assume only newer gens do

Actually I no longer have the rig in my specs tragically, I just never got around to remove it


ATM I’m not ripping any Blu-rays. My collection consists of disc and digital copies through Ultraviolet and Amazon

Bit of looking around and this wiki page should give a complete list of current (and past) GPUs and what they can do for encoding/decoding. Hopefully this helps you out some if you haven't already come across this info.

 

[Durvelle27]

Would a newer Gen APU be sufficient since you get both a CPU and newer R7 IGP

 

[Jetster]

The i3 8350 is the perfect 4k htpc cpu

 

[Durvelle27]

The i3 8350 is the perfect 4k htpc cpu

The entry for intel is just to high

Like mentioned not trying to spend an awful lot. Preferably under $300

I was eye balling a Quad Core APU & a small board with 4GB-8GB of RAM

 

[Jetster]

The entry for intel is just to high

Like mentioned not trying to spend an awful lot. Preferably under $300

I was eye balling a Quad Core APU & a small board with 4GB-8GB of RAM

Yea I saw that after i wrote it. 4k is tough and with plex its not Ideal. Plex is designed to reduce quality when bandwidth and hardware is limited.

 

[Durvelle27]

Yea I saw that after i wrote it. 4k is tough and with plex its not Ideal. Plex is designed to reduce quality when bandwidth and hardware is limited.

Problem is Plex is the only widely used app that supports multiple plateform a out the gate

So doing as much reading as possible

Would a cheap dual core rig and a modern GPU get the job done versus being strictly CPU as it seems even i7s struggle at 4K transcoding.

 

[Jetster]

Problem is Plex is the only widely used app that supports multiple plateform a out the gate

So doing as much reading as possible

Would a cheap dual core rig and a modern GPU get the job done versus being strictly CPU as it seems even i7s struggle at 4K transcoding.

If you just want 4K on the host yes. Depends on which dual core.

What I do is run Kodi for local and Plex to stream. But I dont do 4 k

Keep in mind. A Plex Pass is required for hardware accelerated streaming

https://support.plex.tv/articles/115002178853-using-hardware-accelerated-streaming/

 

[Durvelle27]

Something I just found out which seems to be working pretty good so far
The Plex DirectPlay which basically just sends the raw file to whatever device pulling it no transcoding involved at all. But the device must support the original file.

Playing Fate of the Furious 4K HVEC from the server to my Xbox One S the CPU usage is around 20% and the movie has not buffered any and plays greatly. I’d still have to test on the smart TVs though

Still want to build a dedicated server though