I bought the PG279Q a little over a year ago, sometimes the monitor will not work at all and the buttons will not respond except the on/off button, at first i thought it was due to the extereme OC on the cpu (6700k@5GHz) or the avexir rams which i thought were unstable, unplugging the cables for few minutes fixed the issue, anyways, yesterday the same problem occured, i tried unplugging the cables and waiting few mins, changing from DP to HDMI, changing PCs, I own a second PG279Q and both the PC and the DP cable are working properly, so the problem is from the monitor itself, it just shows a black screen, it flickers when i change settings on nvidia settings (chaging refresh rate or resolution) but it stays on black screen and the buttons will not respond at all.