Yesterday I shut off my
Hello
If you know that the display is working, (you've tested it on another machine or similar) Then the issue is with the machine obviously.
Lets begin by removing all the RAM from the machine, (Unplug first of course, and press the power button so that any remaining power is released)
After you have removed all the ram from the machine, plug it back in and power on, it should BEEP.
Turn off the machine after you have gotten tired of beeping (just turning it on and hearing the beep is enought, if you don't hear a beep there might be a more serious problem, but more on that later)
Plug in one of the Ram modules. And power on again. you should get picture now as long as the machine beeped before, if it doesn't try the other module.
By now you should be getting picture out of the machine, if not, the problem is possibly the video card, cpu or mainboard.
Unplug all the extra devices on the machine, only leave connected, Powersupply, mainboard, cpu, ram, video. disconnect all the cables going to dvd drives etc.
Try turning on again, if you still don't get anything, remove the video card, if possible try another card, power on without the card and turn off again, plug in the card again.
You should have gotten the machine working by now, by trying another video card, if not, the problem is either the cpu or the mainboard.
There is a Clear CMOS jumper near the mainboard battery, removing the battery is not a good way of reseting the bios, best way is to use the jumper on the board.