Monitor won't display anything! Please help!

Wupideedoo

I'm going to try and include all information that I think might be relevant.

The situation was that I was using my computer to watch an episode of TimeWarp. Well apparently my computer had just downloaded and installed some updates that I didn't know about and right in the middle of the episode, my computer rebooted. When it came back on, I could hear all the normal start-up sounds for my computer, except my monitor was still in stand-by.

Now I had recently been prompted to install new Nvidia drivers, which I had done gladly as it mentioned improved performance for multi-card setups, which I've got. This was a few days ago and I can't remember if I had rebooted the computer since then, so that might be the cause/a factor.

I've tried to find information about this online but it turns out it's a very difficult thing to search for. My computer boots, of that I'm sure, but for some reason my computer monitor never leaves stand-by. The only things I've found that mention anything similar are gentlemen who have had motherboards fail, which seems unlikely as there are a slew of other symptoms mentioned which I am not experiencing. Otherwise most results are about computers that simply don't boot. The information might be out there, but since the terminology is so varied, it's near impossible to search for in any productive capacity.

I have not been able to test it with another monitor yet; that will happen tomorrow. Testing with another video card might not be possible, but I will try.

Thanks.

Technicality

If you don't even see the initial BIOS boot up screen when the computer starts, its a hardware problem. Most likely a disconnected, loose or damaged cable, or dying PSU/Video card (edit: or monitor). Possible but less likely to be a dying RAM/Motherboard/CPU (since you say it sounds like its booting up).

When you say it boots, what do you mean exactly? What makes you sure?

Daenris

Do you have onboard video as well? Try hooking your monitor up to the onboard video and then booting up. It's possible that for whatever reason, your setup got forced back to onboard video instead of your installed video card(s).

Also (since you said you had multiple cards) try all of the following:
remove video cards, boot with onboard video
remove 1 card
remove other card, replace first card

See if any of those work.

Wupideedoo

When it booted, I could hear the harddrive go through it's familiar clicks (I've had the PC for nearly 2 years now, I know what the booting up sounds like). Once it was done with that (and far more reliably) I would hear the Windows Login startup sound come through my speakers. And then, to be really sure, I went to my Xbox 360 to see if I could access my media from my PC still, and I could. So it was for sure still booting.

I don't have onboard video. I tried taking out the video cards and I put the secondary card in the primary slot and tried booting from there and it worked.

This actually led to an interesting thing that I have questions about. I was interested to see what the Windows Experience Index had to say abount only one graphics card, and the number actually went up (from a 5.5 to a 6.8). Now, I have put the old primary card back in to the secondary card slot, hooked it all back up and whatnot, and I still only get a 6.8. Is there any way to tell if both are working properly?