Philbar you are quite mistaken if you think for a second your system can max it out at 1680x1050, apparently this game is ridiculously demanding computer wise and not even a core i7 OCed with a gtx 280 can max the game out and not have huge drops in fps in certain areas ( various articles throughout the net that document this ). Wether this is because the game truly is demanding or poorly ported, whatever, that doesn't change the fact that its so demanding.
I'm thinking of just getting the game for the PS3 since its at very reduced prices and I recently got a PS3...I mean so much less hassle, plus the 2 background apps ( 3 if you have steam version ) that is required to be run in the background to play doesn't exactly help smooth things over.