Why does my computer monitor keep saying "no signal"?

i have a compaq pessario desktop and its been acting up lately..i have turn it off n on a few times to get the monitor to work...now its stop coming on all togather. it saying no signal..i check the cable. and monitor on another system..they bothwork...

hey, i got a compaq pressario (desktop) and its started asking up..when i turn it on, the monitor wont come on.. try turning it on n off and sayin no signal and goes into sleep mode...i try unpluging, i even bought a new video card, that didnt work either...

Ok, so my computer has been working fine for awhile now, but the other day I noticed that it was starting to get really slow changing web pages and opening programs and what not. I reset my router, which seemed to help my slow internet, but shortly thereafter...

so my computer was running just fine and i had 2 monitors hooked up and it was going great but i had to completely install the operating system of my computer now i have everything set up the right way (monitors in the right spots and everything) and...

I want to connect my computer to my Samsung LCD TV and people keep saying I need to choose "External Monitor" on my computer for it to work. How do I do so? I am ...show more

What I'm saying is, can I keep my computer, but just trade out the regular pc monitor for a touch screen? Or do I have to have the whole set up?

What I'm saying is, can I keep my computer, but just trade out the regular pc monitor for a touch screen? Or do I have to have the whole set up?

I just recently bought an alienware computer. Sometimes when i turn the computer on, the monitor says "no signal input." Restarting my computer usually does the trick, however I dont like having to hold the power button in or flipping the power...