Can you put pci express x16 2.0 in x16 slot?

Yes, all versions of PCI-Express are backwards compatible. Version 2.0 and 2.1 cards work in regular x16 slots, while version 2.1 slots accept version 2.0, 2.1 and regular x16 cards, there's no compatibility problem either way. Whichever item (motherboard

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