Monitor won't get signal from computer

I built my own PC recently, and everything was going smoothly. I had everything set up was browsing and then *poof* the image went on the monitor. The computer didn't turn off or anything, there were no signs of overheating beforehand, or any freezing, and the computer itself didn't sound as if it were having issues either. The most I was doing was shaking my leg nearby, perhaps my leg sent tremors and threw everything out of whack. The image simply went. I tried to hook up the computer to my TV via HDMI cable thinking it might be either my monitor having the issue, or my vga/DVI adapter, but I got no image there either. The light on my graphics card is green and it seems to be functioning

I have no idea what to do. I didn't alter anything on my system, I've made sure everything is secure. I've ordered a proper DVI cable off Amazon, although I doubt that will do the trick. The HDMI cable was working just fine when I first got it, since it was the first monitor I used before I got the VGA/DVI adapter.