My monitor doesnt detect my PC

[blue4fun]

I have an old alienware computer that i bought in 2001. It has a tv screen monitor that usually has no problems. I had been using the computer every day and the monitor always turned on with the computer. One day i turned on the computer, and the monitor didn't turn on with it. I tried to turn the monitor manually, but after a few seconds, the screen says "Please Wait..." then shows that it is on VGA mode. Lastly, the screen says "No Signal" and stays that way. I don't know whats wrong with it, and i really need to fix it. Please Help!

 

[seumas_beathan]

Do you need a vga/dvi etc cable to connect pc to monitor? if so then check if that is in properly.
Also do you have onboard graphics or are you using a graphics card?

 

[wolfram23]

Also, did you ever clean the dust bunnies out? If not then there is a very good chance the heat sinks are blocked and it overheated last time you used it and died.

Hopefully not, but you never know.

Could be a power supply issue as well.