Help for Monitor

i want my monitor to work i know pretty much everything you need to know about computers, the ONLY problem i have is my MONITOR WONT WORK!

everything on my computer works fine, I want to use my computer, i got a new one but it's not mine and my mom's using it and i have to log on to THIS COMPUTER in order to get it to work.

So the monitor works fine from this computer and doesn't on the other. tried everything i can.

so what do i need to do to get it to work?

and the ONLY thing wrong (and it worked BEFORE) is that we moved the computer to another location in order to give my mom the desk

so SOMETHING is wrong witn it, and i dont KNOW what to do!

so what do i do in order to fix it to get it to work, because i unplugged everything BUT the power supply, and had ONLY the GRAPHICS MODULATOR to be PLUGGED IN

and it won't work,but works on this computer so to any computer techies or whatever you want me to call you, out of desperation and help, WHAT SHOULD I DO TO FIX THIS MONITOR/COMPUTER PROBLEM?

thanks