Does any PCIe slot support NVMe SSD's automatically or do I need

How can I find out what Gen of NVME my machine supports (what will gen 4 nvme work in gen 3 slot tl;dr: The crucial P3 doesn't seem to like the lack of 4 full gen3 lanes, not sure how the nvme standard plays into that I couldn't find williams slot How can I determine the 'Gen-level' era of the laptop SSD NVMe slot? Will a Gen4 device work, and how poorly? It was on sale for the same

williams slot machine From a numbers standpoint, it depends on the speed of your gen4 drive; but if your drive is capable of higher transfer speeds than gen3