1.The computer motherboard is not powered;

　　2.Poor contact of computer CPU;

　　3.Computer machine infected with CIH virus BIOS destructive;

　　4.The computer monitor is powered off or the data cable of the monitor is in poor contact.Additionally,the power cable of the monitor is prone to oxidation and damage after prolonged use of the computer;

　　5.It is necessary to use rubber or other materials to remove the oxide film on the golden finger during inspection and insertion;

　　6.Poor or damaged computer graphics card contact;

　　7.Computer floppy disk,waiting for the computer to start or restart,if the computer appears black screen,enter the system to avoid similar situations.BIOS cancels the floppy disk startup;

　　8.Poor connection of computer memory module.