I think you wil find that most of them do now. The check is to look at the sockets for the cards and see if they have two outputs. Often there is a VGA, usually blue (analogue) and a DVI (digital) usually white, to be seen.
Some cards have dual DVI.
Surface Pro (2017) vs Surface Pro 4
Where HTML5 is headed next
MacBook Pro v Surface Pro 5
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