i just sent my computer in to get a new power source installed and upon return of my computer i hooked it up to a different monitor than the one i normally use and everything was working fine. i bring the computer back up to my school and plug it into my relatively new flat screen LCD monitor and when it starts up, it goes through all of the booting screens, but when windows loads up the screen just goes black with a small blue message box in the middle that reads "ANALOG OUT OF REACH 75.3 kHz / 60 Hz." i have no idea why it says that but i dont know how to go about changing whatever it is that's wrong with it. can someone please help me out here?