Re: Pixel Clock
You'll need a dual-link DVI cable, plugged into a dual-link DVI capable interface to power a 30" LCD (ie. Dell and Apple's 30"). Since current 30" LCD's require dual-link DVI, I'd think they would put a dual-link DVI cable in the box, so yeah it would work.
In regards to the OP, I ran my Dell 2005FPW (1680x1050) on a GeForce4 Ti4200 using DVI in windows and using VGA in linux (upgraded to PCI-E in linux before I had a chance to use DVI in linux on the Ti4200).