Your monitor has a native resolution of 1440x900, aspect ratio 16:10.
Unfortunately if you mean your video is ATI Rage 128 Ultra, this resolution may not be natively supported:http://support.dell.com/support/edocs/vide...ecs_video_modes
For best results, you need to be able to set your video to 1440x900, or another lower one with the 16:10 ratio (which will give larger on-screen images but slightly less clarity due to interpolation).
If your card provides DVI output and you're using this, there are some reports of this giving less resolution choices, so try the VGA connection in this case.
The latest driver update from Dell or ATI may provide more resolutions, but possibly not 1440x900 if this is not considered native to the video chip.
Another possibility you could try is a video utility like PowerStrip:http://www.entechtaiwan.com/util/ps.shtm
That one is a try-before-you-buy shareware type product, so you could see if it enables the correct resolution for you.
If you are completely unable to get the card to provide a suitable 16:10 resolution, you'll either have to compromise on appearance or update to a more current video card.
Edited by Platypus, 22 September 2007 - 09:58 PM.