先把前面那个开关打开，然后FN+F5就会出了， 选系统下载吧 http://support1.lenovo.com.cn/lenovo/wsi/Modules/Driverdownload.aspx?SearchType=1&LogicType=1&MachineId=-6685&SN=&IsBackPage=false&IsSeachOne=true&typename=IdeaPad+Y450
