Edit: Think i solved it! When costomizing the resulution in the Nvida control panel u need to change from 32 bit to 16 bit, then it seems to work! One little thing they seem to have forgotten to mention.
If you're sure that your card's control panel has the resolution you're trying to use as a viable one, then something may have gone wrong during all those installations/uninstallations. The only thing I can propose is to make a new install of everything.