As noted, the reason it says the max resolution is 1920x1200 is likely because the motherboard uses a Single-Link DVI configuration. The CPU's integrated graphics (IGP) apparently supports your resolution, but only with DisplayPort (similar hack on a displayport by motherboard manufacturers)
Quick Reference Guide to 3rd Generation Intel® Core
That limitation doesn't affect dedicated GPUs (e.g. nVidia and AMD graphics cards), so just use one of those and plug your monitor into the GPU and not the motherboard. (I assume you are buying a video card, as people normally don't buy quad-GPU capable motherboards to just get stuck with the IGP...)
As an additional note, make sure the cable attaching your monitor to the GPU supports that resolution (e.g. Dual-link DVI) or you'll get funky artifacts when using your computer.