I don't know DP at all but with a DVI port you need a DVI to VGA Adaptor to connect the analog monitor to the back of the computer, eg;
http://www.mcbworld.com/mcbworld/images/Dvi-to-VGA-adapter2.jpg
It seems there are now DP to VGA adaptors available as well, eg;
http://www.amazon.com/CablesToBuy-DisplayPort-Display-Converter-Adapter/dp/B0026REL8C
Connect them as normal, turn on the computer and Windows 7 should recognise them both.
Hope that helps.
Mark
I have a Dell T7500 Precision workstation. OS is Win 7 Pro with an authorized downgrade to Win XP Pro. Video card is a 512 MB nVidea Quadro FX with a single DVI port and 2 DP ports. I have 2 Samsung 19" monitors with only VGA ports. How do I effectively connect the monitors to the videocard and how do I configure the system for a dual monitor set-up?

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