Symptoms .. All connections on the back are death. Lan (leds off) *Usb service port *Hdmi *Scart rgb *Scart video etc. Nothing works normally. If you have the box connecting to a TV, you see for 1 sec something of stripes on the screen. This repeats until the box has finished its startup cycle. The box itself will start normally, the front leds are operating normally. Then you may have a crystal, Y800 54.000 MHZ problem. You can check whether it with freeze spray. Make sure the crystal is not cooled by the fan, in other words turn the fan off, or lay the cover next to it. Connect the box to a TV, wait for it to start up completely. Wait for a minute, let it warm up. Now, spray the Y800 crystal with freeze spray, you will see an response, a black screen, or something else. Turn the box off and on again. Now you should see that everything works again. However, I recommend replacing the crystal for a new one. Good luck.
