1. Observe that the main board light is not on, the CPU fan is not turned, and the power fan is not turned. No alarm estimates that the motherboard may be bad;
2. The frequency of the CPU that is set in the CMOS free jumper board is incorrect, and it may cause no display failure. In this regard, as long as clear CMOS can be resolved;
3, memory non-oxidation, remove the memory strip with an eraser and then plug it up to see, the general problem can be solved;
4. Firmly press the BIOS chip on the motherboard to make it plug in tightly; if the fault phenomenon is still to be eliminated;
5, replace a reliable host power supply to try; if the failure phenomenon is still the motherboard bus problems, need repair.