Pcie x16 slot into multiple x4 slots

x1, x4 pci Cards Fit Into x16 pci-e Slot can i put pcie x4 in x16 slot The thing is, only one of the PCIe slot is x16, the other one is x4 I have a Radeon RX 580 on the x16 slot, and I plan to put a Radeon RX 570 on the x4 can you use ddr3 in ddr4 slot Next Generation Storage：1*PCIe x4 and 2*PCIe x4 Connectors EZ-Latch：PCIe x16 Slot & Connectors with Quick Release & Screwless Design

canine carnage slot Two types of PCIe slot on an Asus H81M-K motherboard Various slots on a computer motherboard, from top to bottom: PCI Express x4; PCI Express x16; PCI Express