4 USB Port Front I/O

Most better mobo's will have at least 4x usb2 headers and 1x usb3 headers. A single header will support 2x ports. Budget cases are designed with budget mobo's in mind, that may only have 3x usb2 and 1x usb3 total headers, that means 5 rear/1 front usb2 and 1 rear/1 front usb3.