Crysis NOT full screen with HD 5870 in crossfire

I'm having this issue with Crysis and CrysisWarhead, basically when I change the resolution to 1920x1080, a black border shows up around the screen. How do I fix this? Other games are running fine for me.

if u mean it is a window not fullscreen? alt enter

It's in full screen but there are black bars on every side. Nothing to do with the screen itself since other games work fine.

what resolution is your monitor? you most likely have a higher resolution like 2560x1600 or the rare 2048 x 1152 and since your settings it to a lower resolution and have 1:1 pixel mapping set on your getting black borders on all sides.

check your graphics' card control panel and make sure it's using scaling

those bars appear because it is obviously not the native resolution/aspect ratio.

Sounds silly, but do you have the fullscreen option checked?