You cannot. Why and how did you lose the display on the monitor. Is the monitor defective. Any error messages that came up. Is your cable to the monitor damaged or not connected correctly. Have you checked to see if Mobo,Video Card ,Hard Drive is damaged or failed.
What exactly happens when you turn on the computer? Do you have any video
display? Do you hear any beeps?
Is the system on warranty? If you have no video at start-up the problem is
not with Windows and System Restore can not help.