Ignore these fools???!!
You card is way better than mw3 can handle on its highest settings, i have a gt 430 (much worse than yours) and i get 240+ fps with v-sync turned off.
You have a very good graphics card, and the reason it cannot go past 60 fps is because you have v-sync turned on (which limits it to 60fps) and that is all your monitor can display.
at 1440x900 you are lucky to get 40 fps on max graphics, forget about 240+, not even the best graphics cards on the market can do this,
why would you want to get more than 60FPS???