NVR vs PC for 20 cam system

[Video1]

I have 14 older 4 MP cameras around the property. I want to add at least 2 more cams pointing back towards the house, and also a couple of license plate readers and overview cameras at the front of the property. It seems like I could easily build a new PC for what a 32 channel 4k NVR would cost. Any reason not to? Is it a requirement I use an Intel i7 or can I use an AMD Ryzen 7 instead? I've got an old 1050 video card in my current PC that I could swap over so I can get a new video card.

 

[looney2ns]

So, your considering Blue Iris?
Choosing Hardware for Blue Iris | IP Cam Talk

 

[Video1]

So, your considering Blue Iris?
Choosing Hardware for Blue Iris | IP Cam Talk

Thanks for the link. Yes, I would be using Blue Iris. It looks like I need to stick with an Intel CPU. No video card will save me some money. I already have a spare computer case and PSU. I'm a little fuzzy on the type of processor I need however. My 14 older cameras are 4MP. These are currently all run on a substream with my current NVR. I would assume I would do the same thing using a PC. What about the LPR camera? I've seen folks post it should be run at 60 FPS. 18 4MP cameras running on a substream would be about 360 FPS if I run them at 5 FPS on the substream. Then I would use two of the HFW5241E-Z12E 2MP bullet cameras that seem to be popular here, and run those at 124 FPS each. So my total would be 608 FPS. According to the guide you linked to, I would need an i7-8700 CPU. Does that sound correct?