Hmmm just had a scary moment with my 34" UM65
Display port input suddenly went off then started to flash display on/off.
Checked GTX 780 Ti (2nd RMA replacement model brand new 2 months ago).
Checked using another new HDMI cable & got a display straight away.
Turned it off then put the original Display Port cable back in....... now it works just fine again either its very senstive or failing as the cable is a very tight fit tighter than a madonna
All I did was gently knock the table the monitor is sitting on whilst its on
If it fails within 12 months I am not bothered as the place I bought it from have a zero hassle direct RMA replacement service none of this send to LG for repair BS