Ok..Well the PROBLEM with my computer is that when i turn the power button on the computer itself comes on but the monitor does not show anything and also the keyboard and the mouse are not registering. My network card green light shows, i can hear the fan on in the computer, the hard drive comes on, and the cd rom comes on..Does anyone know what kind of problem this is? I think it MAY be the power supply or the motherboard but im not sure which one it is. Any thing will be helpful.Try the basics first.
1. Make sure everything is plugged in, to include the monitor and it's power cable.
2. Clean out the inside of your computer with some air duster. (this just worked for someone with this same problem yesterday actually)
3. Listen. When you BOOT up, do you get any beeps? If so, check your mobo handbook and check the code against the ones in the book. If you don't have the book, post the code (one long two short for example) and the mobo model number here.Well everything is plugged up..I dont have a mobo handbook because it was a computer built for me.I have been having it for over 3 years now. Im going to try and clean it that may work.. but if that does not work any other ideas?No system beeps? Most mobos give at least a single "all's well" beep on boot up.

Try another monitor if you can, or try yours on another computer to test it.

Try reseating your video card. Most have a fan on them, maybe it worked its WAY loose.

If you still get nothing, I'd have to LEAN toward a mobo failure since it's not just video, but your keyboard and mouse as well.