I am possibly dealing with a very similar problem myself.
I have a Samsung Syncmaster 931BW LCD with a GeForce 8800 GTS video card. Not quite the same but similar. With my system everything looks great: games, movies, images, everything but the text displayed in Windows XP (including text within applications run on the OS).
When I look up close the text is clear in some area and fuzzy in others. It looks like some, but not all, of the vertical line segments are spread over more pixels that they should be and appear grey instead of black, resulting in an eye straining out of focus image.
Another observation I have made is when I drag a window in the horizontal direction only, the blury text does a little “dance”. However, when I drag the same window in the vertical direction only, the still blurry text does not “dance”. I used the edge of the desktop as a vertical or horizontal guide.
The problem does not manifest when I use a VGA cable, but is present when I use a DVI cable.
I have tried every thing I can think of with out success: Fresh drivers (for both monitor and video card), resolution changes, Windows font smoothing, different DVI cables...
I could go back to the VGA cable, but that seems to be such a shameful waste.
Does this describe what you are experiencing?
Sorry I have nothing to offer in the way of a solution, just need to get the word out.
Here are my system specs:
Core 2 Duo E6400
ASUS P5B motherboard
Window XP home edition
BFG GeForce 8800 GTS
Samsung Syncmaster 931BW
DVI-D (dual link) cable