What are you trying to do? Do you want to game on the 1440p and have the other 2 for webpages/movies etc up? Because yeah this is fine. Or are you trying to game in surround on all 3 at once? If so you are going to have some complications using mixed resolutions. Usually it will force the 1440p into 1080p for surround, but some people have reported finding ways around this, I don't have enough knowledge on that.