Use for 4K preset P4, CQP 20-25. Smaller value - better quality, but larger size.
If size is important to you, then use VBR or CBR
13:36:53.085: [jim-nvenc: 'advanced_video_recording'] settings:
13:36:53.085: codec: H264
13:36:53.085: rate_control: CQP
13:36:53.085: bitrate: 0
13:36:53.085: cqp: 18
13:36:53.085: keyint: 250
13:36:53.085: preset: p6
13:36:53.085: tuning: hq
13:36:53.085: multipass: qres
13:36:53.085: profile: high
13:36:53.085: width: 3840
13:36:53.085: height: 2160
13:36:53.085: b-frames: 2
13:36:53.085: lookahead: true
13:36:53.085: psycho_aq: true