Help my PC!

I got a new video card the other week and I’m having some issues. Not performance issues, it runs games with ease and opens my Adobe programs in seconds. For some reason I can’t get it to see multiple monitors. Here are the specifics:

My PC: Windows 7 64 bit, 2.4 Ghz Quad Core Processor, 6GB of RAM

The card is a Radeon 5670, it supports DVI, HDMI and Display Port. My main monitor is a 22 inch Dell monitor that came with my computer. It’s got VGA and DVI inputs. I have a HDMI to DVI cable connecting it to the card. So far, so good.

My second monitor is a Wacom Cintiq 12WX. The Wacom plugs into a little converter box and then outputs through a DVI-I port. With my old card I had a DVI to VGA cable running between the Cintiq and the computer. Now I figured I’d just go straight DVI. So I flicked the display switch on the Cintiq to DVI and plugged in my DVI cable (my cable is DVI-D, not sure if that matters).

  

The second that cable is plugged in, my main monitor goes black.

No matter what I do I can’t get the screen to come back until I shut off the computer and remove the second monitor. I’ve tried EVERYTHING to get this up and running.

-I updated my Windows 7 drivers

-I updated the video card drivers

-I reinstalled the Cintiq drivers

-I tried using the DVI to HDMI cord

-I turned the resolution down on the main monitor to see if that would do anything (that was a suggestion from an IT guy at work).

I don’t know what to do, but it’s driving me crazy. I want my second monitor back and I want to use my graphic tablet. There are still a couple of things I’m going to try:

1. Since I know it used to work with the DVI to VGA cord I’m going to try to use a DVI to VGA adapter (borrowed from a friend). I’ll plug that into the card then plug the cord into the adapter.

2. The Cintiq has a DVI-I plug, and so does my video card. I’m thinking about buying a DVI-I to DVI-I cord to see if that works. I’ve been told that doesn’t matter, but I feel like I’ve tried everything else.

Any help would be greatly appreciated.