Reseat the vga cable both ends.
If no help test the monitor and cable on a different machine.
If it works on a different machine your back to the video card.
My monitor displays it's on dvi for about 3 seconds then goes to sleep. However, the display reads it is on dvi & should be on vga. How can I go to an "options menu" to change display from dvi to vga?????

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