if the nvidia driver doesnt support that resolution, dell has OEM drivers for that monitor:
<A HREF="http://www1.us.dell.com/content/learnmore/learnmore.aspx?c=us&cs=555&l=en&s=biz&~id=monitors&~line=desktops&~mode=popup&~series=optix&~tab=other" target="_new">http://www1.us.dell.com/content/learnmore/learnmore.aspx?c=us&cs=555&l=en&s=biz&~id=monitors&~line=desktops&~mode=popup&~series=optix&~tab=other</A>
if you use the non-native 1600x900 resolution the image will either be scaled (bad) or you could try to find a setting that forces the monitor to do 1 to 1 pixel mapping (each pixel of resolution matching up to a screen pixel). the image wouldnt be scaled in that case but you would have black bars on the sides.
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