What is PCI Express? Do PCIe lanes, slots, and versions matter?

What is PCI Express? Do PCIe lanes, slots, and versions matter? can you connect pcie 4 0 in 3 0 slot PCI-E versions are Backwards Compatable it will work all you may get is limited Bandwidth from your PCI-E Slot to your PCI-E Graphics can i use pcie 40 in 50 slot will use an x16 mechanical slot even though the data connection is only x8 Notice 'SLOT 13' are PCIe x16 slots but only Slot 3 has an x8 connection

canadian wild slot It can be challenging to tell the difference between PCIe and SATA connections if you look at the slot on the motherboard can exchange data 4 times faster