Also, are you using sub stream for detection?
Here is my system metrics with an overkill NVR. 9 cameras, 5 4mp, 4 8mp, 15fps, h.264, 1280x720 sub stream for detection, Refurb HP Elite SFF 600 G9 Intel i5-12500 @ 3.00GHz, 32gb ram. Frigate in docker on Debian. qsv-h264 hardware decoding, dual...