12700k Alder Lake Poor HW accelerated performance very poor

Server Version#: 1.25.2.5319

Hi I recently upgraded my Plex server to a 12700k on windows because I heard such good things about intel quick sync and plex. However, I have been quite disappointed with transcoding performance. Using hardware acceleration seems to load the gpu extremely heavily when using encoding. Just one stream of live tv loads the GPU to 80% 2 streams and the server can’t keep up and buffering happens often.

To fix this I found I can uncheck use hardware-accelerated video encoding.

Should this igpu not be a lot more powerful then this? Is 12th gen just not very well supported? I am running the latest version of pms with stated support for 12th gen intel.

Unknown. Obviously, this iGPU is new to Plex (and the world). So, probably not too many people out there to confirm your findings, especially since many run dedicated Plex servers with much cheaper components.

Let us know if you find out anything more though.

This video UHD 750 Plex transcoding performance (quicksync) - YouTube didn’t try your MPEG2TS style example, but still it showed promise for at least UHD 750 when doing HEVC to H264.

even hevc shows similar behavior

although even with hw encoding turned off its still using a ton of the gpu for 1 4k transcode

Im getting 80% gpu usage for 1 1080p transcode to 720p. Something seems way off. Can anyone else confirm similar behavior on 12th gen? Using windows 10 btw.

As others have stated in other places you’ve posted. Windows 10 might be the issue with this new hybrid chip. Windows 11 appears to have a better scheduler implemented for it.

So I tried upgrading to Win 11 with no impact on performance.

I did notice this in the log. I did at one point have an nvidia gpu in the system but that has since been removed. Is this normal?

Jan 19, 2022 22:50:33.400 [24440] DEBUG - [Transcode/72C4DA34-8B57-4507-A34A-6D7257A88FEB] Codecs: testing hevc (decoder) with hwdevice nvdec
Jan 19, 2022 22:50:33.400 [24440] DEBUG - [Transcode/72C4DA34-8B57-4507-A34A-6D7257A88FEB] Codecs: hardware transcoding: testing API nvdec
Jan 19, 2022 22:50:33.400 [24440] ERROR - [Transcode/72C4DA34-8B57-4507-A34A-6D7257A88FEB] [FFMPEG] - Cannot load nvcuda.dll
Jan 19, 2022 22:50:33.400 [24440] ERROR - [Transcode/72C4DA34-8B57-4507-A34A-6D7257A88FEB] [FFMPEG] - Could not dynamically load CUDA
Jan 19, 2022 22:50:33.400 [24440] DEBUG - [Transcode/72C4DA34-8B57-4507-A34A-6D7257A88FEB] Codecs: hardware transcoding: opening hw device failed - probably not supported by this system, error: Unknown error occurred
Jan 19, 2022 22:50:33.400 [24440] DEBUG - [Transcode/72C4DA34-8B57-4507-A34A-6D7257A88FEB] Could not create hardware context for hevc
Jan 19, 2022 22:50:33.400 [24440] DEBUG - [Transcode/72C4DA34-8B57-4507-A34A-6D7257A88FEB] Codecs: testing hevc (decoder) with hwdevice dxva2
Jan 19, 2022 22:50:33.400 [24440] DEBUG - [Transcode/72C4DA34-8B57-4507-A34A-6D7257A88FEB] Codecs: hardware transcoding: testing API dxva2
Jan 19, 2022 22:50:33.400 [24440] ERROR - [Transcode/72C4DA34-8B57-4507-A34A-6D7257A88FEB] [FFMPEG] - Failed to load D3D9 library
Jan 19, 2022 22:50:33.400 [24440] DEBUG - [Transcode/72C4DA34-8B57-4507-A34A-6D7257A88FEB] Codecs: hardware transcoding: opening hw device failed - probably not supported by this system, error: Unknown error occurred
Jan 19, 2022 22:50:33.400 [24440] DEBUG - [Transcode/72C4DA34-8B57-4507-A34A-6D7257A88FEB] Could not create hardware context for hevc