no problem. the 6600GT has at least one DVI link.
take a look at the DVI plug. If it looks like this ::: ::: - then you have single-link DVI that can support up to 1920*1200. If you have a DVI that looks like this :::::::: - then it is a dual-link DVI that supports up to 2560*1600. Either way, your fine.
but as mentioned above, being able to drive your desktop at 1920*1200 is VERY different from being able to game at that resolution. get used to scaling...