I was on my pc today, everything just normal, and when I left my house I shut it down from the start menu. When I came home and tried to turn it on the monitor just says "no signal". I have a graphics card, so I switched to using the on-board graphics card and still "no signal".
Another thing is that it won't power down with the switch anymore. I turned it off by turning off my surge protector. It powers up just fine though, just no signal from the monitor.
I tried swapping out the cable, but I still had the same problem.
When swapping between onboard video and my graphics card I just swapped the cable from one connection to the other, I did not remove the graphics card completely.
When I turn on the computer the lights all come on and the fans spin, but I don't really hear all the noises that sound like the machine is powering up. I don't know if that will help at all, but I thought it could be a clue.
1) Turn off the system from the wall outlet and unplug it.
2) Open your case. Inside, first remove the PCI-E power cables from the graphics card.
3) Gently remove your graphics card. If you feel that you are pulling it too hard out of the PCI-E slot, check for a latch (most mobos have one) and push it down to release.
4) Once the graphics card is completely removed, plug an HDMI/DVI/VGA cable from your motherboard's video output into the monitor you are using.
5) Plug the system back in and make sure the monitor is on. Turn the system on and see if there is signal now.
If your monitor receives signal after these steps I am sorry to say but your graphics card has been damaged. However, you haven't caused the damage (unless you OC the GPU on a card which doesn't permit this in the warranty) so the supplier should refund you if it is in the warranty period (usually 2-3 years).
If you purchased the computer pre-built this may be more difficult, but is still possible to do.
IF you do not receive signal try changing the cable or output you are using. If this still continues make sure all connections are secure. Finally, if nothing seems to work it may be time to return the Motherboard. Please tell me, after you try the steps above, about what occurs.