You can reduce the vertical blanking interval when using a single-link TMDS transmitter to support 1920x1200. All our Mac cards support this resolution on Apple's panels for instance (down to our lowest 7000). In fact, our PC/Windows cards also support this once you've booted the OS. Been this way for years. YMMV with different displays. And generally, I don't believe many (most?) 1920x1200 panels even support Dual Link. Hence shipping the standard single-link DVI-D cable.

Our new Mac X800XT, as well as FireGL X3 cards support Dual Link - this allows you to connect Apple's 30" 2560x1600 display (and others' high resolution DL-DVI displays).

Bruno