gpu and cpu usage, im misunderstanding something.

[glitchgod]

k620 gpu 
Cpu - workstation cpu, not strong at all like 2 core 4 threads.
Use max threads of cpu via transcoding settings, 
most other transcoding setting are default except what it can decode.

Using nvidia-smi and watch as I force a 4k video to 420bit i see the gpu usage hit like 12% max but the cpu is like 75%. I know i have the transcode working as the jellyfin dashboard shows the orange bar to show its transcribing so im misunderstanding something.
How can i flip this? 
like use more gpu please as it stands the desktop uses more ?

|=========================================================================================|
|    0  N/A  N/A            1236      G  /usr/lib/xorg/Xorg                      94MiB |
|    0  N/A  N/A            1774      G  /usr/bin/gnome-shell                    86MiB |
|    0  N/A  N/A          12243      C  /usr/lib/jellyfin-ffmpeg/ffmpeg          77MiB |
+-----------------------------------------------------------------------------------------+

I might be misunderstanding how the gpu and cpu work.

[nyanmisaka]

The K620 (Maxwell) does not support H.265/HEVC. Since 4K video is typically encoded in HEVC, CPU software decoding is unavoidable in such cases.

https://developer.nvidia.com/video-encod...ort-matrix

[glitchgod]

oh okay so the cpu is used to fall back on when the gpu doesnt support something. Okay, time for me to find a converter then