Well the thing of it is the reason for the tearing is that the physical output image is out of sync with the display. It can get very complicated and looking at your specs its hard to say that one component is obviously causing a problem.
Have you tried changing the refresh rate ? You could try tripple buffering the Graphics card in an effort to slow it down which may or may not bring it back into sync, also try upping detail settings AA/AF and ingame graphics settings. If that dosent make a differance then go the other way. Turn the tripple buffering off and turn down the settings/details in an effort to speed things up a bit to get it to fall in sync.