Okay, I realized something after reading Chavo's post, when I have my computer on and my monitor plugged in, it just has a black screen, however, when I unplug the monitor and my computer is on, it says, "Check Signal Cable."
So I'm saying this based on speculation, but, doesn't that mean my video card was sending something to the monitor (therefore, working), but my computer, like Warrior said, has a BIOS misconfiguration or something?
I did try taking out my video card but I don't know how and I'm afraid I'm going to break something lol.