x4 vs x8 vs x16 slots any difference rtx 3060 ti

GPU in PCIEX4 instead of x16 can i put pcie x4 in x16 slot Further, PCIe spec allows downplugging, that is inserting a lower lane count card into a higer lane count slot As such you can safely insert a candy burst slot PCIe slots allow your motherboard to connect with your PC's most critical components and provide key functionality

can you put ddr3 in ddr4 slot Here is AMD's Crossfire compatibility chart to help you understand which cards will work together in crossfire and yes x16 and x4 will work fine