Can't boot into Safe Mode

What OS are you using, Win 7/8/10?

Not that it makes much difference, your only option is to let windows start loading (the screen right after post) then hit the reset button, do this over and over until it pops up "Diagnosing" or some such under the loading image. You will then get a prompt to repair. You can revert to an older restore point. Google is your friend if you get stuck 

Another thing that might work, if your system has more than one display output, let the system go into windows the unplug the Display from one port and move it to the other. It should redetect complete with default refresh rate settings. If not, the option above is all I have for you.

Good luck