There's no video card in either system - the video is either chipset-integrated or soldered onto the mainboard.
There is a version of the 630 to come that will have a separate video chip, so if you want that feature with the newer chipset of the 630 (vs. the 620) wait a bit, assuming it's not going to be needed until August/September.
I have the same issue with the 820 & 830. I am leaning towards the 820 because of the video chip issue. I am no fan of Intel integrated video chips. Now if you are not in a hurry, Dell will have some type of optional video chips available for the 630 & 830 Latitudes later with even DX10 compatibiltiy as a rumour I am looking tonight at a $667 savings on a 820 tonight, and the 830 does not seem to offer me much in improvements that are in important. Or, I might even jump ship for a discontinued Lenovo T60. Decisions, decisions.