Technical help needed.

I kinda need some help with my computer.
Yesterday, I tried to turn it on, but it seemed as if the energy cables were disconnected or something. I then tried to change the hole where is was plugged, and it seemed to work.
Then, when I tried to turn it on again, the video didn't seem to be working, either. The monitor turns on, but it gets no signal from the graphics card. I tried plugging the HDMI in the card's alternate entrance, got nothing. I tried cleaning off any dust inside, nothing. I tried connecting the VGA entrance to see if it was the card's problem and if it would work without it, but I got no results. Can anyone lend me a hand?

Come on. Anybody?

POST beeps?

To give you any hope, it helps to know the PC's make model and year. Also of the computer monitor you use.

I hear Google is a great place to get answers to your questions.

I hear lemonparty.org is a great place to get answers to these types of questions!