There’s generally one or two slots connected directly to the CPU running in x16 or x8 if there’s two and both are connected, 4 lanes linking the CPU to the chipset, and the rest of the slots connect to the chipset and share that same x4 link. If your cpu has 24 lanes (Ryzen do/did a few years ago, Intel might but didn’t a few years ago), the remaining 4 lanes usually go to an NVMe slot
For recipe tracking and “what to buy” I’ve actually had good success with https://grocy.info/
Has really cut down on buying things to use only to get home and find out I already had half of it and forgot
My desktop has a wireless card in an m.2 slot (as do those of my wife and both children), one of my laptops has a SATA m.2 as its only drive because it only has a SATA m.2 slot, another laptop has a SATA m.2 as the scratch drive because it has one NVMe and one SATA, and “the only things you plug into an m.2 slot right now are nvme drives” is such a wild take that I’m baffled as to where it came from
Just as an uninvolved third party, I’m trying to figure out how NVMe entered this response to a question about a SATA to SATA form factor converter
That which is dead can never die