How to determine from command line if NVMe slot is gen 3 or gen 4?

What does the X4 mean in an PCIe Gen X4 NVME drive? can you use a pcie 4 0 nvme in a 3 0 slot a) Any real user with Optiplex 5060 can help confirm which speed does 5060's slot support? b) Which SSD are you using with 5060 and any NVMe can you buy a slot machine For example, a PCIe x4 SSD card can fit in a PCIe x4 or x8 slot, but a PCIe x8 card won't be compatible with an x2 or x4 slot

can you connect pcie 40 in 30 slot That is to say, you can insert a PCIe SSD into a PCIe slot, but you won't be able to fully achieve the fast data transfer speeds of that