The monitor won't last 3 months before it starts flickering on and off.  Don't bother troubleshooting, the problem was this plastic window box they call a computer monitor. If this item received 4 stars then the computer tower is 3.999 stars and the monitor is .001 star.  Like a lemon car,  periphio is a lemon monitor, once you get down the road the engine blows. I did not know they took planned obsolescence down to 2.5 months. It looked like someone glued the ports to the back of the monitor, I could hear them rattling when I took it out of the box. If you want to be replacing your monitor every couple of months, this is the perfect buy for you. Good luck.