Almost never when it comes to AMD, because AMD would need to use at least one displayport for triple monitors. So if you wanted to use AMD, you'd need to get an adapter to convert from displayport (or minidisplayport) to either DVI or HDMI.
I'm not sure if the most recent 600 series Nvidia cards have a limitation like this, but they include a displayport on the card.
But there are special AMD cards with the equivalent of an adapter built-in, but I think they cost more than just buying a regular AMD card + adapter.