NVidia 128 MB DDR Nvidia GeForce FX 5200 highest resolution forum

http://www.nvidia.com/page/pg_20040109440047.html < read the brochure

"•Dual RAMDACs (up to 400 MHz) for display resolutions up to and including 2048×1536 @ 85Hz" make sure your monitor driver and display driver are updated.

upgrading the graphic card driver gave me the best result of 1600 x 1000. Not sure how to upgrade monitor driver though, have looked at Dell's website, couldn't find anything

your using the dvi connector right? not the old vga connector. you may just need to update the grahics card, maybe it doesnt support that exact resolution. there are also programs around that will force resolutions. or you can set up a custom resolution in nvidia control panel.