Graphics Cards

Hi Everyone!I have an nVidia GTS250, running the latest drivers. FSX runs great on my system, high frames (locked at 45), nice and smooth outside views even at busy airports.But i was wondering how heavily FSX relies on the graphics card? I heard it wasnt that much?The reason i ask is that my card has no fan speed control, so its always running at full speed, and is getting really noisy now. Using compressed air the clean the fans isnt making a difference like it used to.I know its not the most powerful card on the market, but as FSX is the only 'game' on my PC, and i dont run any other 3D heavy programs, could i get a lower spec with a smaller fan (or no-fan) card without sacrificing too many frames? I was thinking the 9400GT?I would rather a quieter card than a powerful one that isnt being used to its full potential! :)I have 2 screens running at 1920x1080, but FSX is only ever on one screen (maximised Windowed mode).