These are acceptable units (good performance at the price) however upon receipt, I thought I had two defective ones. The usb3 micro (superspeed) connector AOC designed into the rear of the monitor wasn’t intended to handle the torque of the cable they included (very stiff) and was pulling at an odd angle, so the monitor would connect, then disconnect; the slightest motion or touch on the cable would cause failure. I tried a couple other cables I had on hand and recommend throwing away the ones AOC sends and get something else like: http://a.co/iqAB8eM (amazon of course!) Even though those are not parasite-power (dual usb tail) they power the monitor just fine. Additionally, I opened one monitor up to reflow the solder on one connector which had actually lifted (something I’m quite familiar with in my day job); not something I’d expect an average customer to do, so beware that these refurbs are likely returns from original customers tweaking on the connector due to the original bad cable. They aren’t really as portable, slim or light as the Asus versions my office pals have, but at half the cost, it’s a good extra monitor for a lappy or win-tablet.