There is one thing you need to check. If you have a DYI computer, is the express graphics slot active on the motherboard in setup. Even after I corrected that setting, I still couldn't get anything more on the DVI connection that 1024x768. What fixed the problem for me was to disable the 2nd display clone in ATI Catalyst. Now I have full resolution available of 1650x1050 in Vista SP1. It was interesting that when I installed Ubuntu 8.10 (dual boot) and used the restricted drivers, I got the full resolution automatically.