Custom NVR build/What CPU type for 14-18 1920P, 5MP cameras?

Hi, new post/member looking for some guidance on custom build NVR, hear you guys are experts . We are looking to deploy about 14, 5MP 2592 x 1920 IP cameras, with future expansion maybe to 16 or 18 at best, but since they are 5MP looking to get full use out of them at their full resolution if possible, utilizing blue iris software. As far as live viewing, that would be done remotely once initially set up over LAN, maybe 2 or 3 session/user tops. I was thinking utilizing i5-8400, or Ryzen 5 1600, but I hear Blue Iris can be a CPU hog, what hardware processor type should I be looking for? Thx in advance!