Asus' $4,000 4K monitor goes on sale this month, pushes Retina MacBook to its breaking point

There's no denying that Asus has a real technological marvel on its hands with the newly introduced 31.5-inch 4K monitor that's gracing its Computex 2013 stand. This stunningly sharp IGZO panel can output images and video at a resolution of 3840 x 2160, and what's more, its US release is scheduled for before the end of this month -- a true rarity for Ultra HD panels of any screen size. It does, however, come with a significant and somewhat surprising downside. It's not just the price, which Asus...