1080p/medium/8k xsplit is fine, obs stutters

[beryhhio]

Hi, I have a dedicated streaming pc with the following hardware

Ryzen 7 3700x
16 gb ram ddr4 3200 cl16
nvidia gtx 1050
nvme ssd

The problem is I can easily do 1080p medium 8k bitrate using xsplit, but I can't do the same with obs because the app refuse to use my cores.
Any fix? Or should I just switch to xsplit?

I tried everything, game mode/bar/etc. are all off.
0.4% frames dropped with obs, but the stream is unwatchable because the core 0 capped @ 100% makes things stutter like crazy.

 

[beryhhio]

Yes.
Log:

 

[carlmmii]

No frames lost due to encoding lag.

Why do you have your capture card set for 240fps? That's forcing your CPU to deal with 4x the frames than you're actually recording, since OBS is outputting at 60fps.