For starters, the iMacs haven't been updated to use the nVidia chipset (though there is a model that comes with an nVidia 8800GS graphics card). Second, you have to purchase a mini-DVI adapter separately
No - no iMacs come with any external cabling I believe. That is where they get us in the you know where. I found mine in the refurbished bin at an Apple clearance sale and was really lucky. They no longer have the month end sale.