Is a pure USB 3.0 port fully compatible with USB 2.0 ? My question came when I want to buy a new motherboard. Some motherboards have USB specified as USB 3.0/USB 2.0 which clearly signifies that this port is USB 2.0 compatible. Some motherboards have their USB 3.0 ports specified as USB 3.0 only. Does that mean I might face some compatibility issues for some USB 2.0 devices? Does this differ from USB3.0/USB2.0 ports?