Gateway Zx6971-UB10P AIO appears to not be getting power, it comes on with logo and an overlay that says PC Mode in blue. also gives One short beep code, then immediately goes off and shows No Signal on monitor screen. Have tried a hard reset ( remove power and hold power button 30 sec.) no change. Also appears the tip of power cord wiggles in cord socket (back of unit). All peripherals are disconn., only functioning with mouse/keyboard attached. Cannot find an adequate disassembly schematic way user maunal will not download .
Thanks for any help in advance.