ViewSonic XG275D-4K Just a few years ago, it would have been impossible to find a high-refresh-rate, 27-inch, 4K gaming monitor like the $500 ViewSonic XG275D-4K, a DFR -- dynamic frequency and resolution -- monitor that can operate at 160Hz in its native 4K resolution or 320Hz in a 1080p, 25-inch window. Now, you can choose…

Photo By CNET

Photo By CNET