If you listened a one beep, then the computer mailed, and the CPU is fine. POST Power On Self check A process the computer goes by on starting to assure all is good. while you acquire the black screen, and perfectly nothing else, this is where the request starts. Sometimes the fans and the CPU looks to be functioning.
When this occurs to me, I have an moment advantage as I have a substitute part for essentially any computer element at my tips.

it boot up, it look like it is booting as the CPU fan is functioning and the lights are on. It also gets the CD ROM but it won’t boot from a dc either. sometime it will boot to a black screen and the power switch light will be green and then becomes to orange or amber. all is running. all looks to be functioning but you can’t see anybody on the screen, not even a dashing cursor.

The primary and most apparent reason for a computer looking to run but you cannot assure the video is the monitor. A usual fault is to plug the monitor into the on board video connect while you really have a PCI or AGP video card installed. only move the plug to the right situation. many time you can say if your computer video card is degenerating by checking little tell tale signs. Lines looking or flashing can sometimes happen, yet sometimes nothing finds at all. You may turn your computer on and have the dreadful black screen. You can attempt taking out your video card and utilizing on board video, or substituting the video card to check if that is the problem.