I think your screen is fine, Probably a motherboard issue.
What's you computer, is it old ??
Do you have a working computer you could test the screen on ??
The computer is an old bare bones system.
The monitor basically worked before I switched the bios from card to internal.
I have tried F8 to get into safe mode with no avail.
I suspect that the problem is the resolution is set higher that what the internal will support.