Here is what I know by researching all the specs on your equipment.
The SP2309W Monitor is DVI-D Single Link.
The Gigabyte GeForce 6600GT GV-3D1 Video Card is DVI-I Single Link
The DVI Cable that came with the SP2309W Monitor is DVI-D Single Link
So, if all the connections are Single Link, it should work.
And here are some other specs I looked up, specs you already know:
DVI-D Single Link supports monitor resolutions up to 1920 x 1080 @ 60hz
DVI-D Dual Link supports monitor resolutions up to 2560 x 1600 @60hz
Looking at those specs is how you can tell if your card and/or monitor is a Single or Dual DVI connection. Most of the DVI ports I see on monitors and Video Cards look like DVI-I ports, thats the DVI Multi use port with all the pin holes, for either Single, or Dual, or Analog DVi Cable connections. So staring at that DVI Multi Use Port isn't going to tell you anything except that you need to look at the specs. And locating all those DVI and Monitor specs ain't always easy. Why they make it so hard to find them is beyond me. Its a numbers game, they throw out that big resolution number and leave you wondering if its an analog or digital specification. Its like dating, looking for that perfect match between Monitor and Video Card.
If I see a spec for native resolution 2048 x 1536 @60hz , 75hz, or 85hz, then I'm thinking its analog (VGA). Especially since your monitor does not have the higer DVI-D Dual link connector port...but it does have the Higher Resolution VGA port in addition to the lower resolution DVI-D Single Link connector port.
It seems that you are trying to get VGA (analog) signals thru your DVI (digital only) cable, by believing that you are going to see a 2048 x 1536 resolution with a DVI-D cable that only supports 1920 x 1080. Think again.
So now that you know what DVI connections you really have, you should be able to fix your problem, if you haven't already.
There may be other issues at play here also, you Video Card may not have enough juice from your power supply. Especially if you are running dual monitors.
You might have to upgrade to a bigger power supply. 350watts to 450watts or more.
I hope this helps. And that I haven't posted any erroneous information. If I have, someone please correct me!
I know what I know about this, because for the last two weeks I have been researching AGP Video Cards and DVI connections so that I can find a Computer Video Card to go along with my new Samsung 26" widescreen TV/Monitor. Its amazing now on VGA, but I want to try out the Digital DVI connection, I hear and read that its better than Analog (VGA). I hope I get this done before my head spins off.
Avis Anna