I know graphics cards are still incredibly expensive and hard to find, but I thought I would see if the users of the Plex forums had any recommendations for a card that can transcode UHD well might be occasionally available at a decent price.
Why do you want to transcode 4K? You would be better off making a optimized version for non 4K TVs and remote viewing. It is a lot less resource intensive transcoding a 1080p video file. Not only that a fast CPU is still needed for HDR tone mapping.
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Because I don’t want to store 2 copies of every UHD movie and ask the user to select the correct one. I’d rather just have it work.
I did some testing last night and I am pretty close to having enough horsepower with my CPU, some movies will transcode at 1.0x to 1.2x and only pause once or twice. Others will stay below 1x and pause a lot. I am thinking it depends on how much there is going on in the scene. Interestingly, my CPU stays at about 80%, so maybe I can squeeze a little more juice out somewhere?
Anyway, I would still like to know if there are any decent cards out there that will help with transcoding. I have an old GTX 470 laying around, would I get any benefit of putting that in the server?
Just FYI, if you have a 4K and 1080p, the user dose not have to select which copy to play. Plex will use the one that is closes to the resolution of the TV. For remote users, Plex will use the lower resolution copy and transcode it even if the remote user has a 4K TV.
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So, I found out that my GTX 470 is not capable of handling H265, so that is out.
You want a GPU that can decode 10-bit H.265 4:2:0 and encode to H.264. See Nvidia Video Encode and Decode GPU Support Matrix.
Elpamsoft has transcoding performance information for Nvidia GPUs.
Note that HDR to SDR Tonemapping is only partially supported on Nvidia GPUs for PMS on Windows.
Suggest you search the forum for applicable threads, as it appears tonemapping is quite CPU intensive.
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Excellent! Thank you for the helpful post. It seems that the GTX 1650 would be the biggest bang for the buck as it supports even more formats than the 1070 Ti that I currently have in my workstation.
Given the experience I am currently having, I don’t think i am going to need tonemapping. Everything that I am using to stream remotely is either an iphone, ipad or appleTV and they all seem to handle HDR just fine. When I first started experimenting with UHD on my Roku, I know the colors looked really washed out, at this point, the tonemapping had not yet been released for plex. Everything on my iDevices looks fine, even when transcoding down to 1080p or lower. It’s just that I am getting some stuttering as I mentioned above. Maybe I am mistaken in my understanding and it is actually tonemapping to these devices and my CPU is just handling it, feel free to let me know if this is the case.
The 1070 Ti should work just fine. The 1650 supports decoding HEVC 4:4:4, but I’m not aware of any movies/shows released in that format. All my 4K HDR media is HEVC 4:2:0 10-bit.
If Plex is transcoding HDR video, then you want tonemapping. Plex transcodes video to H.264 8-bit SDR. Without tonemapping, the colors will be off/washed out. Some videos looks worse than others, but the colors will still be incorrect.
Some Plex clients can tonemap and scale video by themselves, without involving the server (the server shows direct play / direct stream). I believe the iPhone client can do this (I don’t have an iPhone with which to test). Plex for Windows/Mac can tonemap/scale 4K HDR video. Both it and the Plex iPhone app use the same underlying video player, mpv.io.
Yeah, I guess you are right. I forced my ipad to transcode to 1080p and turned off tonemapping in the settings and it is definitely washed out.
So, if I am almost there with tonemapping and transcoding with just my CPU (i7-4790k), would adding a GPU take the transcoding load off of the CPU so that it had more headroom for tonemapping? …or does it not work that way? My 1070 is currently being utilized to power 3 monitors for my work machine. I can’t really use that one at this point.
Bumping this to see if anyone can answer my last question. Still looking into getting a card.
I picked up a 1650 with the TU106 chip. We’ll see how it goes.
https://www.techpowerup.com/gpu-specs/asus-tuf-gtx-1650-gaming-oc-gddr6.b8267
It seems that the Turing Chip has tone mapping baked in. Hopefully some day Plex will be able to utilize it.
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