depends how big of monitors we're talking. Big ones sometimes require 2 DVI inputs. If they are 24 in or smaller, then 1 DVI per monitor. So search for 2 cards that dual output DVI or 1 card that has 4 DVI, the latter will be hella expensive. The former you can probably get for cheap. Quality of the card is another matter. Are you a pro user or just a beginner. Personally for 2D CAD I don't think its worth spending money on expensive pro cards. For 3D CAD it could be worth it.