1) just power, high voltage charging sound, while the power indicator is green, after about 5-10 seconds after the light turns orange, and accompanied by the loss of hypertension creak La La "sound. At this time probably can be judged that the display 15-pin USB data cable line or field sync signal line (13 or 14-pin) have a disconnection of a display mistakenly believe that the host does not have sent the signal, after 4-5 seconds automatically enter a low energy state.

2) power high-voltage charge of the sound, even if you remove the signal line, power indicator light is always green. This situation is generally the line scan circuit failure, did not produce high voltage.

3) when power is high voltage charge of the sound, no image on the screen, remove the signal line, the power indicator for a while turn to orange, accompanied by the sound of high-voltage discharge. This case to the circuit failure, the general is not coupled with an operating voltage of the CRT, then you can look at the CRT filament is lit. Is also possible that the gate voltage is not coupled.