Moniter tuirns off after boot, and no signal afterwards

Virus shouldn't cause this, did you do anything on your PC recently? (download drivers or the like)

Sounds like its failing as the graphics card is put to real use. That puts graphics card and psu on top of the suspect list.

Are you using onboard graphics, or a video card?

Can you get into Windows in Safe mode?

Do you have another psu to swap in?

How old is your machine and have you ever noticed any thing prior to this problem like a odd noise on occasion?

Is the noise mechanical or electrical? Sounds like a whine or a click, or what?

A whining, high-pitched noise, kinda like a sci-fi ray gun will be the power supply usually, or the motherboard. Did you check where the sound is coming from? Could be from the monitor also, have you tried a different monitor?