PCIe x1 Card Not Working in PCIe x16 Slot

Can I put a 16x graphics card in a 4x slot and it still work? can you put pcie 4x in 16x slot Please Note:- You cannot connect the GPU Riser to your USB port The usb cable is just used can you put ddr3 in ddr4 slot If you have limited expansion slots on your motherboard and all you have available is an

candy dreams_ sweet planet slot why its not doing it in the x4 slot is the card will be pulling less power as its basically bottlenecked by only getting 14 the data sent to it