Monitor isn't starting and is making a buzzing sound

Hi, recently my monitor has been making some sort of quiet buzzing/screeching sound which goes away after 30 sec or a min. But now my monitor isn't starting at all, i usually have to turn the power on the monitor off and on a few times before it works. Sometimes my monitor works right away but usually when i turn on my PC it makes a screeching sound and then doesn't work, the light is blue which means it's recieving a signal so i'm not sure what is happening. Yes i have checked my power cables and they are all connected properly, plz help!!

How old is it? More than 5 years? If so, sounds like its dieing. Probably cheaper getting a new one than repairing.