Just got a refurb'd U2711 to replace a dead 2709W.  Dell didn't send a dual link DVI-D cable.  So I had to buy a dvi-d dual link off ebay (not happy - should have been supplied) and still when I adjust the resolution to 2560x1440 it is blurry/grainy.  Even followed ATI's graphic driver uninstall reinstall instructions but still the same issue.  Now stuck with 1650x1050 not happy at all!  The cable is correct so not sure why this is not working!!

Specs:

Video Card: HIS 3870X2 (has 2 DVI outputs that support res up to 2560x1600)

PC: e8500, P45-DS3, 8GB RAM, Win7 x64 and latest ATI 10.9 Catalyst drivers.