Does it require 16x? Previous-gen video cards were often connected to risers that only provided 1x, and lots of "normal" systems (with a bit of expansion) don'

Does it require 16x? Previous-gen video cards were often connected to risers that only provided 1x, and lots of "normal" systems (with a bit of expansion) don't have enough PCI Express lanes to give 16 lanes to any one device.