I have the same box, but with the 32 core CPU and fewer NVMe drives. I've not poked at all the PCIe slots yet, but all that I've looked at are in NUMA node 1. This includes the on board M.2 slots. It is in NPS=4 mode.
Mine goes only up to 2 NUMA nodes (as shown in numactl --hardware), despite setting NPS4 in BIOS. I guess it's because I have only 2 x 8-core chiplets enabled (?)
