Off the top of my head, it could be a few things. First, have you tried unhooking the power cord from the monitor and then hooking it back in? (I know...simple, but sometimes that's all it takes) If that doesn't do anything, it could be a video card.

Have you installed anything lately?

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::XSGfX::
::My dA::

Another simple but must do check...make sure your video card is seated properly (especially if you've opened your case recently). Make sure the monitor cable is connected properly, could be a little loose.

If you have another computer, try plugging the monitor giving you issues into it. If it works, you can narrow down the problem to that one PC versus the monitor itself. (that would be a good troubleshoot, if possible)

I remember i left the computer on for botting (diablo 2 game). After i remember waking up and walked away for a few minutes, then when i came back and the screen was blue and it said something about logging off windows to prevent damage or damage to windows. So then i restarted the computer thinking that everything would go back to normal..but it didnt thats when the screen didnt turn on when i restarted.

Is your monitor actually not working, or do you mean when you turn your computer on it hangs at the XP logo or a blue screen?

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ok when i turn on my computer everything is alright but after the windows screen the monitor turns off saying that there is no conection or no signal, i can still hear the sounds but i cant see anything. all the monitor cables are connected fine but i still cant see anything.

Thats the picture of what happened about the Blue screen after that i tried to restart and then thats when the the screen didn't turn on with the start up

http://en.wikipedia.org/wiki/Image:W..._2000_BSoD.png

I would recommend:

- Trying to boot your system in 'Safe mode' to see if you get different tunr out
- Usng a boot disk for your O/S. If you have a floppy drive, easy task...you can download the boot disk for your sysem from XS HERE
- Try booting up w/your XP disc in recovery mode, that will/should fix any damaged or missing files.