|"I turned it back on and it will not act right"|
That's not very descriptive. We need to know exactly what happens when you try to power on the system. Do you see the normal lights on the case? Do you hear the fans spinning inside the case? Do you hear any beeps from inside the case? You should hear one beep which basically means "all is well". If you hear no beeps or a series of beeps, you have a hardware problem.
"Even when I turn off the tower there is no change in the lighting on the monitor"
"Lighting" on the monitor? If it's not receiving a signal from the video card, nothing will change in the "lighting".