1, The power light does not light and the fan does not rotate:
First ,confirm that the power indicator on the adapter is lit. If not, replace another right power ,and then confirm whether it is OK again.
The second step, replace the right motherboard , confirm whether it is OK
2、The power light is on, the fan is rotating, the hard disk indicator is flashing, and the external display can display:
A. Connect the external display, press DEL key to enter the BIOS COMS setting interface, select the chipset item, select system agent (SA) configuration in the chipset drop-down option, select in the system agent (SA) configuration sub-item in the graphics configuration item, select the LCD control item in the children of the graphics configuration, and then select the LCD panel type item from the submenu of the LCD control item, then select the appropriate resolution in this item, and finally press F10 to save and exit;
B. Confirm that the screen line is loose or damaged, re-insert the screen line or replace it;
C. Replace the tested display and check if there is any problem with the display.