No signal detected

[CosmoK]

Hello, I had my computer running for at least a year and now I can't get a signal to my monitor. I have tried multiple monitors and cables. I have tried multiple video cards. I tried moving the ram around and putting it back in. I tried taking out my motherboard's battery and putting it back in after a couple of minutes. Still I have no luck and no idea what to try next. Any ideas of what the problem could be, or how to fix it?

Edit: Also all the fans and lights appear to be working.

 

[Proximon]

When you are describing something like this you have to be pretty clear. There are things we would look for if we were there that would give us clues about what is going on.

The first of those would be sound.
Does it sound as if your computer is booting up? Is the hard drive making noise?

Does the hard drive activity light flicker?

Is the fan on the CPU spinning?

Here are some more thoughts to help you and us:
http://www.tomshardware.com/forum/264823-31-progess-troubleshooting