Are you enabling AA via the nVidia drivers (and if in the drivers, are you setting any of the enhancements/extra features on?), or in the game itself? And are you using any overscan/custom resolution timing/etc settings? Those would be the first places I'd start looking. Also it might be relevant what operating system/driver version you're using.

It's a bug in some games, which use a quad to render a fullscreen texture to screen (very common approach for post-processing).
The problem comes from the fact that texels don't map to pixels 1:1 (this was fixed in DX10), but rather they are shifted by 0.5 pixels: http://msdn.microsoft.com/en-us/library/windo … v=vs.85%29.aspx

The problem gets worse as you enable AA, causing rounding errors to completely miss a row of pixels (their quad coordinates simply don't map to the screen properly).

I have enabled AA in the options of NFS and, in case of Unreal, using the nVidia control panel, because it is an older title. The resolution is a typical 1024*768 px onto a screen of the same size.

This in an interesting article, Scali. I can see a faint border even with anti-aliasing OFF.

Well, first thing obviously: why use regular AA? You have downsampling (see GeDoSaTo) and post-processing AA available for a reason. Not everything works otherwise.

SweetFX can change that border into a 1px black border, but only for DX9-11 games and anything else will need wrappers.