Well as I currently hold the award for useless video cabling (!)
Simple HDMI-DVI cable for one and VGA-VGA for the other connection.
Does this have the integrated 8400/8600M card?
Tip with the XPS is to connect all the cables with EVERYTHING switched off then power up the monitors then the laptop.
Watch out for noise on both signals though (this is the XPS 1330 but the 1530 has similar issues)
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