I've been running an xpenology server since 2015 with DSM 5.1 until last year when Plex required a transition to DSM 6 with x64 packages. I then upgraded to DSM 6.1 with Jun's 1.02 loader and had been fine with that. Wanting to get more performance, I decided to upgrade my CPU from an i3-4130T to a Xeon E3 1285L V4, the best/latest CPU supported by my ASRock E3C226D2I motherboard, which has Intel Quick Sync support. As this was a significant change, I decided to change to upgrade to DSM 6.2.2 and take advantage of HW transcoding support in Plex too.
Installation and migration went fine--I used existing serial/mac from an older Synology 415+. I checked that the Dev/Dri folders existed indicating that HW transcoding was supported. As a Plex Pass user, I enabled hardware transcoding support on the server. I initiated a stream on a device and the Plex dashboard showed that HW transcoding started and minimal spikes in CPU usage. However, the stream never actually played--it was continually buffering and would do so for several minutes and never started. I ultimately disabled HW accelerated transcoding and went back to software/CPU only based transcoding, which starts playing immediately.
I understand that quality may differ while using HW transcoding, but in my case, it doesn't seem to work/start. Am I missing something here? Do i need to enable or add any additional drivers? Is this Xeon CPU not supported for HW accelerated transcoding via Intel Quick Sync?
TLDR
-upgraded CPU to Xeon E3 1285L V4 from I3-4130T
-upgraded to DSM 6.2.2 with 1.04b loader for 918+ platform
-HW transcoding supported and enabled on Plex server
-with HW acceleration enabled on Plex server, stream continually buffers and never actually starts; wind up disabling HW transcoding
-what gives?
My server hardware:
ASRock E3C226D2I
Intel Xeon E3 1285L V4 / Noctua NH-D9L HSF
Crucial 16GB (2x8GB) DDR3 ECC RAM (unbuffered)
4x3TB WD RED drives
XFX XTR 550W PSU
Fractal Design Node 304