The main reasons for the spontaneous shutdown of the computer are considered to be mechanical pollution of the cooling systems and problems with the video card used. The latter problem requires the intervention of specialists, but with the first one you can try to figure it out yourself.
Lack of response to keyboard commands, the instantaneous disappearance of the display and the continued hum of the system unit symbolize problems with the video card used in the computer. But the most common reason for spontaneous computer shutdown is shutdown due to overheating, which is a protective reaction of the processor. The value of this parameter can be changed in the BIOS settings in the Power Management group (by default it is 70 degrees Celsius). To fix this type of problem, it is enough to check the degree of dustiness of the fan blades and the cooler grill and clean it. Another reason for the spontaneous shutdown of the computer may be the contamination of the computer motherboard and slots. The recommended action in this case is to blow off the dust. It is worth paying attention to the possibility of flowing air access to the system unit in order to avoid the repetition of unpleasant situations. It is also possible that one of the motherboard nodes fails. Determination of the cause in some cases is also possible by a visual method: remove the side cover and check the condition of the capacitors. The flat surface of the cross-cut cylinders must not be broken. Any violation of the plane is a warning about the need for qualified repair and re-soldering of the system unit. Do not forget to check the most obvious things - the continuity of the power wires and the continuity of the power supply in the network. Accidentally hitting a wire can cause the computer to shut down spontaneously, and power outages require the use of stabilizers and uninterruptible power supplies.
