My immediate thought is that the on-board graphics chip isn't man enough to drive the screen but that shouldn't really be the case as the PC is quite a high spec. Have you tried downloading the latest drivers from the Dell site? The resolution you've chosen (1280x1024) is correct for that screen.
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Do you know that we're all in line for succession to the throne? Really?
Well, if forty-eight million, two hundred thousand, seven hundred and one people died I'd be Queen.