computer randomly freezes!, says no video signal

[Firefoxett]

hi im typing this from my laptop because my desktop is freezing over nearly every 5min. 

12:12
as i start it up it boots just like usual, and brings me to the typical ms(xp) login, i choose my name and log in and it seems to run fine, (mcafee pops up as usual)
12:14
i begin to do any task internet, game, etc and it runs fluently.
12:17
watching video on youtube
12:20
going good, loging on to online game...
12:26
running quite well...
12:28
message appears (no signal input check video cable)

so thats the issue, out of the blue it will say that
the computer is still running fine, and the cables are tightly in

any input would be much apriciated

[smiling politely]

This might not be of much help, but there could be a short in your monitor cable.

Or there could be a dust issue. Try unhooking it, use air duster on it and the connection to make sure there's no dust, and try plugging it back in.

[Firefoxett]

i just did that, still turns off randomly...
pritty shure its not a connection problem, as it seems to stop all processes when it happens..

[patio]

A short in a video cable will produce those symptoms.
Or you may want to try unplugging the monitor from the wall socket after powering down the machine.
Then re-boot and re-set your video settings and see if this helps...