Problem with PC and Monitor

Hello,

I am having a problem with my PC and monitors. Really the problem is not any of the monitors, but it is with the PC itself. I have a CPU by eMachines and When I turn on the PC, The PC will run and it will not power up the monitor or keyboard. I have checked all connections and everything is connected properly. I tried other monitors and it is doing the same thing. I know that there is something wrong with the connection between the PC and monitor because when I turn on the monitor when it is not connected to the PC, it will display "No Signal". When I connected it again to the PC, I got nothing at all.

Also, when I turned on my PC, the lights on the keybard would light up and I am getting no lights on the keyboard. The only light I get from the keyboard is when I plug it in to the PC and they will blink 3 times. I also checked the monitor and keyboard cables and they are fine also. I am starting to think that there is a problem with some of my inputs because the monitor and keyboard will not power up, but the USB inputs, mouse, etc still work. Any help will be appreciated.