Monitor turns itself off!

Ok, heres the problem. I start the computer up, log into it, and sometimes get to use it for 5 minutes, but then the Monitor just switches off on its own accord, never had any trouble before, only srated doing it recently, had it about a year and a half, i have cleaned all the ports etc seems ok at the moment, just wandering if the cables could be to blame, vid card etc, any help extremely appreciated.

Used to have the same sort of problem...

you may want to make sure the GFX Card is in the motherboard properly and not loose as when i used to have the problem i knew next to nothing about computers and kicking it would kinda make it come back on again lol

But yeah try and make sure the GFX Card is in properly(Dont kick it  ) or if you can try another GFX Card in there.

- Fred

This could be from heat also, if the graphics card is caked with dust and heating up in 5 minutes it may be killing it off.  Check it out if its full clean it out with some canned air.  Also pull the video card out and reseat it. 

I forgot to say that when the monitor turns off, it dispays the message "no signal" if that makes any difference!

yah then the monitor is not turning off that means that the video card stopped transmitting a signal to the monitor