No video signal on monitor

Hey there,
The seniors over at my place just picked up a used PC that actually looks like it's in pretty decent shape—but there's one major catch: once I get everything hooked up, I'm getting absolutely nothing on the screen. It’s running an NVIDIA GeForce 6600 Pro, and while all the fans are spinning up just fine, the computer isn't showing any signs of life on the display. I've already tried swapping between two different monitors and testing both video outputs, but still, total silence. I honestly haven't a clue what might be causing this, so if anyone has any advice or ideas, I'd really appreciate it.

If you've already tested both monitors and neither worked, then there's a 99% chance the issue is with your graphics card..

To be absolutely sure, I'd suggest swapping out the current card for something else in your PCI Express slot.. Basically, pull out that NVIDIA GeForce 6600 Pro and pop in a different one.. Just make sure the replacement uses the same pcie slot as the NVIDIA GeForce 6600 Pro did. Then, just see if you get an image on the screen or not..

Man, I don't have a spare graphics card on hand right now. Is there any other way to troubleshoot this? One more thing—that red LED under the power button is staying lit constantly.

What motherboard are we looking at here, and what's the rest of the build like?