HowTo install & configure Windows 11 in a VM on Proxmox VE 7.1 - step-by-step

Good question. Win11 + BI will run on 4 cores if you only have a handful of cameras and you are not doing anything heavy like facial recognition, HD recording, high frame rate streaming, etc. The fact Windows can run on 2 cores and BI requires 4 cores does not mean we need to provide the sum of cores. Usually we go with the highest-required minimum-denominator which is 4 cores for BI in our case (2, 4 = 4 it is not 2+4).

If you have multiple cameras and are doing some heavy lifting in terms of processing even 8 cores might be border line.

It is easy to increase the number of cores in a VM, therefore starting with 4 is a good starting point.