Does your video card have a software gamma/brightness control, that may have been reset? Right click on an open area of the desktop, select Properties, then the Settings tab and the Advanced button, and poke around. DirectX itself doesn't have a screen brightness control, that I know of.


If your brightness and contrast are both maxed, it is unlikely that the monitor is properly calibrated.
'Brightness' sets the black point (how dark black is), which can be done exactly. 'Contrast' adjusts the overall luminosity of the screen (how bright white is), which should not effect the black point. A site I bookmarked is no longer there, but I found it cached at Google (minus the pictures, though);
Accurate Image Manipulation for Desktop Publishing

Is your monitor still under warranty? If you set the black point properly, but can not increase the Contrast enough to display white as white, you should consider getting it repaired. Check it on a different computer / video card, if possible.